text: #! /usr/bin/env python2.6
  # -*- coding: latin-1 -*-
  """Generate Python documentation in HTML or text for interactive use.
  
  In the Python interpreter, do "from pydoc import help" to provide online
  help.  Calling help(thing) on a Python object documents the object.
  
  Or, at the shell command line outside of Python:
  
  Run "pydoc <name>" to show documentation on something.  <name> may be
  the name of a function, module, package, or a dotted reference to a
  class or function within a module or module in a package.  If the
  argument contains a path segment delimiter (e.g. slash on Unix,
  backslash on Windows) it is treated as the path to a Python source file.
  
  Run "pydoc -k <keyword>" to search for a keyword in the synopsis lines
  of all available modules.
  
  Run "pydoc -p <port>" to start an HTTP server on a given port on the
  local machine to generate documentation web pages.
  
  Run "pydoc -w <name>" to write out the HTML documentation for a module
  to a file named "<name>.html".
  
  Module docs for core modules are assumed to be in
  
      http://docs.python.org/library/
  
  This can be overridden by setting the PYTHONDOCS environment variable
  to a different URL or to a local directory containing the Library
  Reference Manual pages.
  """
  
  __author__ = "Ka-Ping Yee <ping@lfw.org>"
  __date__ = "26 February 2001"
  
  __version__ = "$Revision: 83492 $"
  __credits__ = """Guido van Rossum, for an excellent programming language.
  Tommy Burnette, the original creator of manpy.
  Paul Prescod, for all his work on onlinehelp.
  Richard Chamberlain, for the first implementation of textdoc.
  """
  
  # Known bugs that can't be fixed here:
  #   - imp.load_module() cannot be prevented from clobbering existing
  #     loaded modules, so calling synopsis() on a binary module file
  #     changes the contents of any existing module with the same name.
  #   - If the __file__ attribute on a module is a relative path and
  #     the current directory is changed with os.chdir(), an incorrect
  #     path will be displayed.
  
  import sys, imp, os, re, types, inspect, __builtin__, pkgutil
  from repr import Repr
  from string import expandtabs, find, join, lower, split, strip, rfind, rstrip
  from traceback import extract_tb
  try:
      from collections import deque
  except ImportError:
      # Python 2.3 compatibility
      class deque(list):
          def popleft(self):
              return self.pop(0)
  
  # --------------------------------------------------------- common routines
  
  def pathdirs():
      """Convert sys.path into a list of absolute, existing, unique paths."""
      dirs = []
      normdirs = []
      for dir in sys.path:
          dir = os.path.abspath(dir or '.')
          normdir = os.path.normcase(dir)
          if normdir not in normdirs and os.path.isdir(dir):
              dirs.append(dir)
              normdirs.append(normdir)
      return dirs
  
  def getdoc(object):
      """Get the doc string or comments for an object."""
      result = inspect.getdoc(object) or inspect.getcomments(object)
      return result and re.sub('^ *\n', '', rstrip(result)) or ''
  
  def splitdoc(doc):
      """Split a doc string into a synopsis line (if any) and the rest."""
      lines = split(strip(doc), '\n')
      if len(lines) == 1:
          return lines[0], ''
      elif len(lines) >= 2 and not rstrip(lines[1]):
          return lines[0], join(lines[2:], '\n')
      return '', join(lines, '\n')
  
  def classname(object, modname):
      """Get a class name and qualify it with a module name if necessary."""
      name = object.__name__
      if object.__module__ != modname:
          name = object.__module__ + '.' + name
      return name
  
  def isdata(object):
      """Check if an object is of a type that probably means it's data."""
      return not (inspect.ismodule(object) or inspect.isclass(object) or
                  inspect.isroutine(object) or inspect.isframe(object) or
                  inspect.istraceback(object) or inspect.iscode(object))
  
  def replace(text, *pairs):
      """Do a series of global replacements on a string."""
      while pairs:
          text = join(split(text, pairs[0]), pairs[1])
          pairs = pairs[2:]
      return text
  
  def cram(text, maxlen):
      """Omit part of a string if needed to make it fit in a maximum length."""
      if len(text) > maxlen:
          pre = max(0, (maxlen-3)//2)
          post = max(0, maxlen-3-pre)
          return text[:pre] + '...' + text[len(text)-post:]
      return text
  
  _re_stripid = re.compile(r' at 0x[0-9a-f]{6,16}(>+)$', re.IGNORECASE)
  def stripid(text):
      """Remove the hexadecimal id from a Python object representation."""
      # The behaviour of %p is implementation-dependent in terms of case.
      return _re_stripid.sub(r'\1', text)
  
  def _is_some_method(obj):
      return inspect.ismethod(obj) or inspect.ismethoddescriptor(obj)
  
  def allmethods(cl):
      methods = {}
      for key, value in inspect.getmembers(cl, _is_some_method):
          methods[key] = 1
      for base in cl.__bases__:
          methods.update(allmethods(base)) # all your base are belong to us
      for key in methods.keys():
          methods[key] = getattr(cl, key)
      return methods
  
  def _split_list(s, predicate):
      """Split sequence s via predicate, and return pair ([true], [false]).
  
      The return value is a 2-tuple of lists,
          ([x for x in s if predicate(x)],
           [x for x in s if not predicate(x)])
      """
  
      yes = []
      no = []
      for x in s:
          if predicate(x):
              yes.append(x)
          else:
              no.append(x)
      return yes, no
  
  def visiblename(name, all=None):
      """Decide whether to show documentation on a variable."""
      # Certain special names are redundant.
      _hidden_names = ('__builtins__', '__doc__', '__file__', '__path__',
                       '__module__', '__name__', '__slots__', '__package__')
      if name in _hidden_names: return 0
      # Private names are hidden, but special names are displayed.
      if name.startswith('__') and name.endswith('__'): return 1
      if all is not None:
          # only document that which the programmer exported in __all__
          return name in all
      else:
          return not name.startswith('_')
  
  def classify_class_attrs(object):
      """Wrap inspect.classify_class_attrs, with fixup for data descriptors."""
      def fixup(data):
          name, kind, cls, value = data
          if inspect.isdatadescriptor(value):
              kind = 'data descriptor'
          return name, kind, cls, value
      return map(fixup, inspect.classify_class_attrs(object))
  
  # ----------------------------------------------------- module manipulation
  
  def ispackage(path):
      """Guess whether a path refers to a package directory."""
      if os.path.isdir(path):
          for ext in ('.py', '.pyc', '.pyo'):
              if os.path.isfile(os.path.join(path, '__init__' + ext)):
                  return True
      return False
  
  def source_synopsis(file):
      line = file.readline()
      while line[:1] == '#' or not strip(line):
          line = file.readline()
          if not line: break
      line = strip(line)
      if line[:4] == 'r"""': line = line[1:]
      if line[:3] == '"""':
          line = line[3:]
          if line[-1:] == '\\': line = line[:-1]
          while not strip(line):
              line = file.readline()
              if not line: break
          result = strip(split(line, '"""')[0])
      else: result = None
      return result
  
  def synopsis(filename, cache={}):
      """Get the one-line summary out of a module file."""
      mtime = os.stat(filename).st_mtime
      lastupdate, result = cache.get(filename, (0, None))
      if lastupdate < mtime:
          info = inspect.getmoduleinfo(filename)
          try:
              file = open(filename)
          except IOError:
              # module can't be opened, so skip it
              return None
          if info and 'b' in info[2]: # binary modules have to be imported
              try: module = imp.load_module('__temp__', file, filename, info[1:])
              except: return None
              result = (module.__doc__ or '').splitlines()[0]
              del sys.modules['__temp__']
          else: # text modules can be directly examined
              result = source_synopsis(file)
              file.close()
          cache[filename] = (mtime, result)
      return result
  
  class ErrorDuringImport(Exception):
      """Errors that occurred while trying to import something to document it."""
      def __init__(self, filename, exc_info):
          exc, value, tb = exc_info
          self.filename = filename
          self.exc = exc
          self.value = value
          self.tb = tb
  
      def __str__(self):
          exc = self.exc
          if type(exc) is types.ClassType:
              exc = exc.__name__
          return 'problem in %s - %s: %s' % (self.filename, exc, self.value)
  
  def importfile(path):
      """Import a Python source file or compiled file given its path."""
      magic = imp.get_magic()
      file = open(path, 'r')
      if file.read(len(magic)) == magic:
          kind = imp.PY_COMPILED
      else:
          kind = imp.PY_SOURCE
      file.close()
      filename = os.path.basename(path)
      name, ext = os.path.splitext(filename)
      file = open(path, 'r')
      try:
          module = imp.load_module(name, file, path, (ext, 'r', kind))
      except:
          raise ErrorDuringImport(path, sys.exc_info())
      file.close()
      return module
  
  def safeimport(path, forceload=0, cache={}):
      """Import a module; handle errors; return None if the module isn't found.
  
      If the module *is* found but an exception occurs, it's wrapped in an
      ErrorDuringImport exception and reraised.  Unlike __import__, if a
      package path is specified, the module at the end of the path is returned,
      not the package at the beginning.  If the optional 'forceload' argument
      is 1, we reload the module from disk (unless it's a dynamic extension)."""
      try:
          # If forceload is 1 and the module has been previously loaded from
          # disk, we always have to reload the module.  Checking the file's
          # mtime isn't good enough (e.g. the module could contain a class
          # that inherits from another module that has changed).
          if forceload and path in sys.modules:
              if path not in sys.builtin_module_names:
                  # Avoid simply calling reload() because it leaves names in
                  # the currently loaded module lying around if they're not
                  # defined in the new source file.  Instead, remove the
                  # module from sys.modules and re-import.  Also remove any
                  # submodules because they won't appear in the newly loaded
                  # module's namespace if they're already in sys.modules.
                  subs = [m for m in sys.modules if m.startswith(path + '.')]
                  for key in [path] + subs:
                      # Prevent garbage collection.
                      cache[key] = sys.modules[key]
                      del sys.modules[key]
          module = __import__(path)
      except:
          # Did the error occur before or after the module was found?
          (exc, value, tb) = info = sys.exc_info()
          if path in sys.modules:
              # An error occurred while executing the imported module.
              raise ErrorDuringImport(sys.modules[path].__file__, info)
          elif exc is SyntaxError:
              # A SyntaxError occurred before we could execute the module.
              raise ErrorDuringImport(value.filename, info)
          elif exc is ImportError and extract_tb(tb)[-1][2]=='safeimport':
              # The import error occurred directly in this function,
              # which means there is no such module in the path.
              return None
          else:
              # Some other error occurred during the importing process.
              raise ErrorDuringImport(path, sys.exc_info())
      for part in split(path, '.')[1:]:
          try: module = getattr(module, part)
          except AttributeError: return None
      return module
  
  # ---------------------------------------------------- formatter base class
  
  class Doc:
      def document(self, object, name=None, *args):
          """Generate documentation for an object."""
          args = (object, name) + args
          # 'try' clause is to attempt to handle the possibility that inspect
          # identifies something in a way that pydoc itself has issues handling;
          # think 'super' and how it is a descriptor (which raises the exception
          # by lacking a __name__ attribute) and an instance.
          if inspect.isgetsetdescriptor(object): return self.docdata(*args)
          if inspect.ismemberdescriptor(object): return self.docdata(*args)
          try:
              if inspect.ismodule(object): return self.docmodule(*args)
              if inspect.isclass(object): return self.docclass(*args)
              if inspect.isroutine(object): return self.docroutine(*args)
          except AttributeError:
              pass
          if isinstance(object, property): return self.docproperty(*args)
          return self.docother(*args)
  
      def fail(self, object, name=None, *args):
          """Raise an exception for unimplemented types."""
          message = "don't know how to document object%s of type %s" % (
              name and ' ' + repr(name), type(object).__name__)
          raise TypeError, message
  
      docmodule = docclass = docroutine = docother = docproperty = docdata = fail
  
      def getdocloc(self, object):
          """Return the location of module docs or None"""
  
          try:
              file = inspect.getabsfile(object)
          except TypeError:
              file = '(built-in)'
  
          docloc = os.environ.get("PYTHONDOCS",
                                  "http://docs.python.org/library")
          basedir = os.path.join(sys.exec_prefix, "lib",
                                 "python"+sys.version[0:3])
          if (isinstance(object, type(os)) and
              (object.__name__ in ('errno', 'exceptions', 'gc', 'imp',
                                   'marshal', 'posix', 'signal', 'sys',
                                   'thread', 'zipimport') or
               (file.startswith(basedir) and
                not file.startswith(os.path.join(basedir, 'site-packages')))) and
              object.__name__ not in ('xml.etree', 'test.pydoc_mod')):
              if docloc.startswith("http://"):
                  docloc = "%s/%s" % (docloc.rstrip("/"), object.__name__)
              else:
                  docloc = os.path.join(docloc, object.__name__ + ".html")
          else:
              docloc = None
          return docloc
  
  # -------------------------------------------- HTML documentation generator
  
  class HTMLRepr(Repr):
      """Class for safely making an HTML representation of a Python object."""
      def __init__(self):
          Repr.__init__(self)
          self.maxlist = self.maxtuple = 20
          self.maxdict = 10
          self.maxstring = self.maxother = 100
  
      def escape(self, text):
          return replace(text, '&', '&amp;', '<', '&lt;', '>', '&gt;')
  
      def repr(self, object):
          return Repr.repr(self, object)
  
      def repr1(self, x, level):
          if hasattr(type(x), '__name__'):
              methodname = 'repr_' + join(split(type(x).__name__), '_')
              if hasattr(self, methodname):
                  return getattr(self, methodname)(x, level)
          return self.escape(cram(stripid(repr(x)), self.maxother))
  
      def repr_string(self, x, level):
          test = cram(x, self.maxstring)
          testrepr = repr(test)
          if '\\' in test and '\\' not in replace(testrepr, r'\\', ''):
              # Backslashes are only literal in the string and are never
              # needed to make any special characters, so show a raw string.
              return 'r' + testrepr[0] + self.escape(test) + testrepr[0]
          return re.sub(r'((\\[\\abfnrtv\'"]|\\[0-9]..|\\x..|\\u....)+)',
                        r'<font color="#c040c0">\1</font>',
                        self.escape(testrepr))
  
      repr_str = repr_string
  
      def repr_instance(self, x, level):
          try:
              return self.escape(cram(stripid(repr(x)), self.maxstring))
          except:
              return self.escape('<%s instance>' % x.__class__.__name__)
  
      repr_unicode = repr_string
  
  class HTMLDoc(Doc):
      """Formatter class for HTML documentation."""
  
      # ------------------------------------------- HTML formatting utilities
  
      _repr_instance = HTMLRepr()
      repr = _repr_instance.repr
      escape = _repr_instance.escape
  
      def page(self, title, contents):
          """Format an HTML page."""
          return '''
  <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
  <html><head><title>Python: %s</title>
  </head><body bgcolor="#f0f0f8">
  %s
  </body></html>''' % (title, contents)
  
      def heading(self, title, fgcol, bgcol, extras=''):
          """Format a page heading."""
          return '''
  <table width="100%%" cellspacing=0 cellpadding=2 border=0 summary="heading">
  <tr bgcolor="%s">
  <td valign=bottom>&nbsp;<br>
  <font color="%s" face="helvetica, arial">&nbsp;<br>%s</font></td
  ><td align=right valign=bottom
  ><font color="%s" face="helvetica, arial">%s</font></td></tr></table>
      ''' % (bgcol, fgcol, title, fgcol, extras or '&nbsp;')
  
      def section(self, title, fgcol, bgcol, contents, width=6,
                  prelude='', marginalia=None, gap='&nbsp;'):
          """Format a section with a heading."""
          if marginalia is None:
              marginalia = '<tt>' + '&nbsp;' * width + '</tt>'
          result = '''<p>
  <table width="100%%" cellspacing=0 cellpadding=2 border=0 summary="section">
  <tr bgcolor="%s">
  <td colspan=3 valign=bottom>&nbsp;<br>
  <font color="%s" face="helvetica, arial">%s</font></td></tr>
      ''' % (bgcol, fgcol, title)
          if prelude:
              result = result + '''
  <tr bgcolor="%s"><td rowspan=2>%s</td>
  <td colspan=2>%s</td></tr>
  <tr><td>%s</td>''' % (bgcol, marginalia, prelude, gap)
          else:
              result = result + '''
  <tr><td bgcolor="%s">%s</td><td>%s</td>''' % (bgcol, marginalia, gap)
  
          return result + '\n<td width="100%%">%s</td></tr></table>' % contents
  
      def bigsection(self, title, *args):
          """Format a section with a big heading."""
          title = '<big><strong>%s</strong></big>' % title
          return self.section(title, *args)
  
      def preformat(self, text):
          """Format literal preformatted text."""
          text = self.escape(expandtabs(text))
          return replace(text, '\n\n', '\n \n', '\n\n', '\n \n',
                               ' ', '&nbsp;', '\n', '<br>\n')
  
      def multicolumn(self, list, format, cols=4):
          """Format a list of items into a multi-column list."""
          result = ''
          rows = (len(list)+cols-1)/cols
          for col in range(cols):
              result = result + '<td width="%d%%" valign=top>' % (100/cols)
              for i in range(rows*col, rows*col+rows):
                  if i < len(list):
                      result = result + format(list[i]) + '<br>\n'
              result = result + '</td>'
          return '<table width="100%%" summary="list"><tr>%s</tr></table>' % result
  
      def grey(self, text): return '<font color="#909090">%s</font>' % text
  
      def namelink(self, name, *dicts):
          """Make a link for an identifier, given name-to-URL mappings."""
          for dict in dicts:
              if name in dict:
                  return '<a href="%s">%s</a>' % (dict[name], name)
          return name
  
      def classlink(self, object, modname):
          """Make a link for a class."""
          name, module = object.__name__, sys.modules.get(object.__module__)
          if hasattr(module, name) and getattr(module, name) is object:
              return '<a href="%s.html#%s">%s</a>' % (
                  module.__name__, name, classname(object, modname))
          return classname(object, modname)
  
      def modulelink(self, object):
          """Make a link for a module."""
          return '<a href="%s.html">%s</a>' % (object.__name__, object.__name__)
  
      def modpkglink(self, data):
          """Make a link for a module or package to display in an index."""
          name, path, ispackage, shadowed = data
          if shadowed:
              return self.grey(name)
          if path:
              url = '%s.%s.html' % (path, name)
          else:
              url = '%s.html' % name
          if ispackage:
              text = '<strong>%s</strong>&nbsp;(package)' % name
          else:
              text = name
          return '<a href="%s">%s</a>' % (url, text)
  
      def markup(self, text, escape=None, funcs={}, classes={}, methods={}):
          """Mark up some plain text, given a context of symbols to look for.
          Each context dictionary maps object names to anchor names."""
          escape = escape or self.escape
          results = []
          here = 0
          pattern = re.compile(r'\b((http|ftp)://\S+[\w/]|'
                                  r'RFC[- ]?(\d+)|'
                                  r'PEP[- ]?(\d+)|'
                                  r'(self\.)?(\w+))')
          while True:
              match = pattern.search(text, here)
              if not match: break
              start, end = match.span()
              results.append(escape(text[here:start]))
  
              all, scheme, rfc, pep, selfdot, name = match.groups()
              if scheme:
                  url = escape(all).replace('"', '&quot;')
                  results.append('<a href="%s">%s</a>' % (url, url))
              elif rfc:
                  url = 'http://www.rfc-editor.org/rfc/rfc%d.txt' % int(rfc)
                  results.append('<a href="%s">%s</a>' % (url, escape(all)))
              elif pep:
                  url = 'http://www.python.org/dev/peps/pep-%04d/' % int(pep)
                  results.append('<a href="%s">%s</a>' % (url, escape(all)))
              elif text[end:end+1] == '(':
                  results.append(self.namelink(name, methods, funcs, classes))
              elif selfdot:
                  results.append('self.<strong>%s</strong>' % name)
              else:
                  results.append(self.namelink(name, classes))
              here = end
          results.append(escape(text[here:]))
          return join(results, '')
  
      # ---------------------------------------------- type-specific routines
  
      def formattree(self, tree, modname, parent=None):
          """Produce HTML for a class tree as given by inspect.getclasstree()."""
          result = ''
          for entry in tree:
              if type(entry) is type(()):
                  c, bases = entry
                  result = result + '<dt><font face="helvetica, arial">'
                  result = result + self.classlink(c, modname)
                  if bases and bases != (parent,):
                      parents = []
                      for base in bases:
                          parents.append(self.classlink(base, modname))
                      result = result + '(' + join(parents, ', ') + ')'
                  result = result + '\n</font></dt>'
              elif type(entry) is type([]):
                  result = result + '<dd>\n%s</dd>\n' % self.formattree(
                      entry, modname, c)
          return '<dl>\n%s</dl>\n' % result
  
      def docmodule(self, object, name=None, mod=None, *ignored):
          """Produce HTML documentation for a module object."""
          name = object.__name__ # ignore the passed-in name
          try:
              all = object.__all__
          except AttributeError:
              all = None
          parts = split(name, '.')
          links = []
          for i in range(len(parts)-1):
              links.append(
                  '<a href="%s.html"><font color="#ffffff">%s</font></a>' %
                  (join(parts[:i+1], '.'), parts[i]))
          linkedname = join(links + parts[-1:], '.')
          head = '<big><big><strong>%s</strong></big></big>' % linkedname
          try:
              path = inspect.getabsfile(object)
              url = path
              if sys.platform == 'win32':
                  import nturl2path
                  url = nturl2path.pathname2url(path)
              filelink = '<a href="file:%s">%s</a>' % (url, path)
          except TypeError:
              filelink = '(built-in)'
          info = []
          if hasattr(object, '__version__'):
              version = str(object.__version__)
              if version[:11] == '$' + 'Revision: ' and version[-1:] == '$':
                  version = strip(version[11:-1])
              info.append('version %s' % self.escape(version))
          if hasattr(object, '__date__'):
              info.append(self.escape(str(object.__date__)))
          if info:
              head = head + ' (%s)' % join(info, ', ')
          docloc = self.getdocloc(object)
          if docloc is not None:
              docloc = '<br><a href="%(docloc)s">Module Docs</a>' % locals()
          else:
              docloc = ''
          result = self.heading(
              head, '#ffffff', '#7799ee',
              '<a href=".">index</a><br>' + filelink + docloc)
  
          modules = inspect.getmembers(object, inspect.ismodule)
  
          classes, cdict = [], {}
          for key, value in inspect.getmembers(object, inspect.isclass):
              # if __all__ exists, believe it.  Otherwise use old heuristic.
              if (all is not None or
                  (inspect.getmodule(value) or object) is object):
                  if visiblename(key, all):
                      classes.append((key, value))
                      cdict[key] = cdict[value] = '#' + key
          for key, value in classes:
              for base in value.__bases__:
                  key, modname = base.__name__, base.__module__
                  module = sys.modules.get(modname)
                  if modname != name and module and hasattr(module, key):
                      if getattr(module, key) is base:
                          if not key in cdict:
                              cdict[key] = cdict[base] = modname + '.html#' + key
          funcs, fdict = [], {}
          for key, value in inspect.getmembers(object, inspect.isroutine):
              # if __all__ exists, believe it.  Otherwise use old heuristic.
              if (all is not None or
                  inspect.isbuiltin(value) or inspect.getmodule(value) is object):
                  if visiblename(key, all):
                      funcs.append((key, value))
                      fdict[key] = '#-' + key
                      if inspect.isfunction(value): fdict[value] = fdict[key]
          data = []
          for key, value in inspect.getmembers(object, isdata):
              if visiblename(key, all):
                  data.append((key, value))
  
          doc = self.markup(getdoc(object), self.preformat, fdict, cdict)
          doc = doc and '<tt>%s</tt>' % doc
          result = result + '<p>%s</p>\n' % doc
  
          if hasattr(object, '__path__'):
              modpkgs = []
              for importer, modname, ispkg in pkgutil.iter_modules(object.__path__):
                  modpkgs.append((modname, name, ispkg, 0))
              modpkgs.sort()
              contents = self.multicolumn(modpkgs, self.modpkglink)
              result = result + self.bigsection(
                  'Package Contents', '#ffffff', '#aa55cc', contents)
          elif modules:
              contents = self.multicolumn(
                  modules, lambda key_value, s=self: s.modulelink(key_value[1]))
              result = result + self.bigsection(
                  'Modules', '#ffffff', '#aa55cc', contents)
  
          if classes:
              classlist = map(lambda key_value: key_value[1], classes)
              contents = [
                  self.formattree(inspect.getclasstree(classlist, 1), name)]
              for key, value in classes:
                  contents.append(self.document(value, key, name, fdict, cdict))
              result = result + self.bigsection(
                  'Classes', '#ffffff', '#ee77aa', join(contents))
          if funcs:
              contents = []
              for key, value in funcs:
                  contents.append(self.document(value, key, name, fdict, cdict))
              result = result + self.bigsection(
                  'Functions', '#ffffff', '#eeaa77', join(contents))
          if data:
              contents = []
              for key, value in data:
                  contents.append(self.document(value, key))
              result = result + self.bigsection(
                  'Data', '#ffffff', '#55aa55', join(contents, '<br>\n'))
          if hasattr(object, '__author__'):
              contents = self.markup(str(object.__author__), self.preformat)
              result = result + self.bigsection(
                  'Author', '#ffffff', '#7799ee', contents)
          if hasattr(object, '__credits__'):
              contents = self.markup(str(object.__credits__), self.preformat)
              result = result + self.bigsection(
                  'Credits', '#ffffff', '#7799ee', contents)
  
          return result
  
      def docclass(self, object, name=None, mod=None, funcs={}, classes={},
                   *ignored):
          """Produce HTML documentation for a class object."""
          realname = object.__name__
          name = name or realname
          bases = object.__bases__
  
          contents = []
          push = contents.append
  
          # Cute little class to pump out a horizontal rule between sections.
          class HorizontalRule:
              def __init__(self):
                  self.needone = 0
              def maybe(self):
                  if self.needone:
                      push('<hr>\n')
                  self.needone = 1
          hr = HorizontalRule()
  
          # List the mro, if non-trivial.
          mro = deque(inspect.getmro(object))
          if len(mro) > 2:
              hr.maybe()
              push('<dl><dt>Method resolution order:</dt>\n')
              for base in mro:
                  push('<dd>%s</dd>\n' % self.classlink(base,
                                                        object.__module__))
              push('</dl>\n')
  
          def spill(msg, attrs, predicate):
              ok, attrs = _split_list(attrs, predicate)
              if ok:
                  hr.maybe()
                  push(msg)
                  for name, kind, homecls, value in ok:
                      push(self.document(getattr(object, name), name, mod,
                                         funcs, classes, mdict, object))
                      push('\n')
              return attrs
  
          def spilldescriptors(msg, attrs, predicate):
              ok, attrs = _split_list(attrs, predicate)
              if ok:
                  hr.maybe()
                  push(msg)
                  for name, kind, homecls, value in ok:
                      push(self._docdescriptor(name, value, mod))
              return attrs
  
          def spilldata(msg, attrs, predicate):
              ok, attrs = _split_list(attrs, predicate)
              if ok:
                  hr.maybe()
                  push(msg)
                  for name, kind, homecls, value in ok:
                      base = self.docother(getattr(object, name), name, mod)
                      if (hasattr(value, '__call__') or
                              inspect.isdatadescriptor(value)):
                          doc = getattr(value, "__doc__", None)
                      else:
                          doc = None
                      if doc is None:
                          push('<dl><dt>%s</dl>\n' % base)
                      else:
                          doc = self.markup(getdoc(value), self.preformat,
                                            funcs, classes, mdict)
                          doc = '<dd><tt>%s</tt>' % doc
                          push('<dl><dt>%s%s</dl>\n' % (base, doc))
                      push('\n')
              return attrs
  
          attrs = filter(lambda data: visiblename(data[0]),
                         classify_class_attrs(object))
          mdict = {}
          for key, kind, homecls, value in attrs:
              mdict[key] = anchor = '#' + name + '-' + key
              value = getattr(object, key)
              try:
                  # The value may not be hashable (e.g., a data attr with
                  # a dict or list value).
                  mdict[value] = anchor
              except TypeError:
                  pass
  
          while attrs:
              if mro:
                  thisclass = mro.popleft()
              else:
                  thisclass = attrs[0][2]
              attrs, inherited = _split_list(attrs, lambda t: t[2] is thisclass)
  
              if thisclass is __builtin__.object:
                  attrs = inherited
                  continue
              elif thisclass is object:
                  tag = 'defined here'
              else:
                  tag = 'inherited from %s' % self.classlink(thisclass,
                                                             object.__module__)
              tag += ':<br>\n'
  
              # Sort attrs by name.
              try:
                  attrs.sort(key=lambda t: t[0])
              except TypeError:
                  attrs.sort(lambda t1, t2: cmp(t1[0], t2[0]))    # 2.3 compat
  
              # Pump out the attrs, segregated by kind.
              attrs = spill('Methods %s' % tag, attrs,
                            lambda t: t[1] == 'method')
              attrs = spill('Class methods %s' % tag, attrs,
                            lambda t: t[1] == 'class method')
              attrs = spill('Static methods %s' % tag, attrs,
                            lambda t: t[1] == 'static method')
              attrs = spilldescriptors('Data descriptors %s' % tag, attrs,
                                       lambda t: t[1] == 'data descriptor')
              attrs = spilldata('Data and other attributes %s' % tag, attrs,
                                lambda t: t[1] == 'data')
              assert attrs == []
              attrs = inherited
  
          contents = ''.join(contents)
  
          if name == realname:
              title = '<a name="%s">class <strong>%s</strong></a>' % (
                  name, realname)
          else:
              title = '<strong>%s</strong> = <a name="%s">class %s</a>' % (
                  name, name, realname)
          if bases:
              parents = []
              for base in bases:
                  parents.append(self.classlink(base, object.__module__))
              title = title + '(%s)' % join(parents, ', ')
          doc = self.markup(getdoc(object), self.preformat, funcs, classes, mdict)
          doc = doc and '<tt>%s<br>&nbsp;</tt>' % doc
  
          return self.section(title, '#000000', '#ffc8d8', contents, 3, doc)
  
      def formatvalue(self, object):
          """Format an argument default value as text."""
          return self.grey('=' + self.repr(object))
  
      def docroutine(self, object, name=None, mod=None,
                     funcs={}, classes={}, methods={}, cl=None):
          """Produce HTML documentation for a function or method object."""
          realname = object.__name__
          name = name or realname
          anchor = (cl and cl.__name__ or '') + '-' + name
          note = ''
          skipdocs = 0
          if inspect.ismethod(object):
              imclass = object.im_class
              if cl:
                  if imclass is not cl:
                      note = ' from ' + self.classlink(imclass, mod)
              else:
                  if object.im_self is not None:
                      note = ' method of %s instance' % self.classlink(
                          object.im_self.__class__, mod)
                  else:
                      note = ' unbound %s method' % self.classlink(imclass,mod)
              object = object.im_func
  
          if name == realname:
              title = '<a name="%s"><strong>%s</strong></a>' % (anchor, realname)
          else:
              if (cl and realname in cl.__dict__ and
                  cl.__dict__[realname] is object):
                  reallink = '<a href="#%s">%s</a>' % (
                      cl.__name__ + '-' + realname, realname)
                  skipdocs = 1
              else:
                  reallink = realname
              title = '<a name="%s"><strong>%s</strong></a> = %s' % (
                  anchor, name, reallink)
          if inspect.isfunction(object):
              args, varargs, varkw, defaults = inspect.getargspec(object)
              argspec = inspect.formatargspec(
                  args, varargs, varkw, defaults, formatvalue=self.formatvalue)
              if realname == '<lambda>':
                  title = '<strong>%s</strong> <em>lambda</em> ' % name
                  argspec = argspec[1:-1] # remove parentheses
          else:
              argspec = '(...)'
  
          decl = title + argspec + (note and self.grey(
                 '<font face="helvetica, arial">%s</font>' % note))
  
          if skipdocs:
              return '<dl><dt>%s</dt></dl>\n' % decl
          else:
              doc = self.markup(
                  getdoc(object), self.preformat, funcs, classes, methods)
              doc = doc and '<dd><tt>%s</tt></dd>' % doc
              return '<dl><dt>%s</dt>%s</dl>\n' % (decl, doc)
  
      def _docdescriptor(self, name, value, mod):
          results = []
          push = results.append
  
          if name:
              push('<dl><dt><strong>%s</strong></dt>\n' % name)
          if value.__doc__ is not None:
              doc = self.markup(getdoc(value), self.preformat)
              push('<dd><tt>%s</tt></dd>\n' % doc)
          push('</dl>\n')
  
          return ''.join(results)
  
      def docproperty(self, object, name=None, mod=None, cl=None):
          """Produce html documentation for a property."""
          return self._docdescriptor(name, object, mod)
  
      def docother(self, object, name=None, mod=None, *ignored):
          """Produce HTML documentation for a data object."""
          lhs = name and '<strong>%s</strong> = ' % name or ''
          return lhs + self.repr(object)
  
      def docdata(self, object, name=None, mod=None, cl=None):
          """Produce html documentation for a data descriptor."""
          return self._docdescriptor(name, object, mod)
  
      def index(self, dir, shadowed=None):
          """Generate an HTML index for a directory of modules."""
          modpkgs = []
          if shadowed is None: shadowed = {}
          for importer, name, ispkg in pkgutil.iter_modules([dir]):
              modpkgs.append((name, '', ispkg, name in shadowed))
              shadowed[name] = 1
  
          modpkgs.sort()
          contents = self.multicolumn(modpkgs, self.modpkglink)
          return self.bigsection(dir, '#ffffff', '#ee77aa', contents)
  
  # -------------------------------------------- text documentation generator
  
  class TextRepr(Repr):
      """Class for safely making a text representation of a Python object."""
      def __init__(self):
          Repr.__init__(self)
          self.maxlist = self.maxtuple = 20
          self.maxdict = 10
          self.maxstring = self.maxother = 100
  
      def repr1(self, x, level):
          if hasattr(type(x), '__name__'):
              methodname = 'repr_' + join(split(type(x).__name__), '_')
              if hasattr(self, methodname):
                  return getattr(self, methodname)(x, level)
          return cram(stripid(repr(x)), self.maxother)
  
      def repr_string(self, x, level):
          test = cram(x, self.maxstring)
          testrepr = repr(test)
          if '\\' in test and '\\' not in replace(testrepr, r'\\', ''):
              # Backslashes are only literal in the string and are never
              # needed to make any special characters, so show a raw string.
              return 'r' + testrepr[0] + test + testrepr[0]
          return testrepr
  
      repr_str = repr_string
  
      def repr_instance(self, x, level):
          try:
              return cram(stripid(repr(x)), self.maxstring)
          except:
              return '<%s instance>' % x.__class__.__name__
  
  class TextDoc(Doc):
      """Formatter class for text documentation."""
  
      # ------------------------------------------- text formatting utilities
  
      _repr_instance = TextRepr()
      repr = _repr_instance.repr
  
      def bold(self, text):
          """Format a string in bold by overstriking."""
          return join(map(lambda ch: ch + '\b' + ch, text), '')
  
      def indent(self, text, prefix='    '):
          """Indent text by prepending a given prefix to each line."""
          if not text: return ''
          lines = split(text, '\n')
          lines = map(lambda line, prefix=prefix: prefix + line, lines)
          if lines: lines[-1] = rstrip(lines[-1])
          return join(lines, '\n')
  
      def section(self, title, contents):
          """Format a section with a given heading."""
          return self.bold(title) + '\n' + rstrip(self.indent(contents)) + '\n\n'
  
      # ---------------------------------------------- type-specific routines
  
      def formattree(self, tree, modname, parent=None, prefix=''):
          """Render in text a class tree as returned by inspect.getclasstree()."""
          result = ''
          for entry in tree:
              if type(entry) is type(()):
                  c, bases = entry
                  result = result + prefix + classname(c, modname)
                  if bases and bases != (parent,):
                      parents = map(lambda c, m=modname: classname(c, m), bases)
                      result = result + '(%s)' % join(parents, ', ')
                  result = result + '\n'
              elif type(entry) is type([]):
                  result = result + self.formattree(
                      entry, modname, c, prefix + '    ')
          return result
  
      def docmodule(self, object, name=None, mod=None):
          """Produce text documentation for a given module object."""
          name = object.__name__ # ignore the passed-in name
          synop, desc = splitdoc(getdoc(object))
          result = self.section('NAME', name + (synop and ' - ' + synop))
  
          try:
              all = object.__all__
          except AttributeError:
              all = None
  
          try:
              file = inspect.getabsfile(object)
          except TypeError:
              file = '(built-in)'
          result = result + self.section('FILE', file)
  
          docloc = self.getdocloc(object)
          if docloc is not None:
              result = result + self.section('MODULE DOCS', docloc)
  
          if desc:
              result = result + self.section('DESCRIPTION', desc)
  
          classes = []
          for key, value in inspect.getmembers(object, inspect.isclass):
              # if __all__ exists, believe it.  Otherwise use old heuristic.
              if (all is not None
                  or (inspect.getmodule(value) or object) is object):
                  if visiblename(key, all):
                      classes.append((key, value))
          funcs = []
          for key, value in inspect.getmembers(object, inspect.isroutine):
              # if __all__ exists, believe it.  Otherwise use old heuristic.
              if (all is not None or
                  inspect.isbuiltin(value) or inspect.getmodule(value) is object):
                  if visiblename(key, all):
                      funcs.append((key, value))
          data = []
          for key, value in inspect.getmembers(object, isdata):
              if visiblename(key, all):
                  data.append((key, value))
  
          modpkgs = []
          modpkgs_names = set()
          if hasattr(object, '__path__'):
              for importer, modname, ispkg in pkgutil.iter_modules(object.__path__):
                  modpkgs_names.add(modname)
                  if ispkg:
                      modpkgs.append(modname + ' (package)')
                  else:
                      modpkgs.append(modname)
  
              modpkgs.sort()
              result = result + self.section(
                  'PACKAGE CONTENTS', join(modpkgs, '\n'))
  
          # Detect submodules as sometimes created by C extensions
          submodules = []
          for key, value in inspect.getmembers(object, inspect.ismodule):
              if value.__name__.startswith(name + '.') and key not in modpkgs_names:
                  submodules.append(key)
          if submodules:
              submodules.sort()
              result = result + self.section(
                  'SUBMODULES', join(submodules, '\n'))
  
          if classes:
              classlist = map(lambda key_value: key_value[1], classes)
              contents = [self.formattree(
                  inspect.getclasstree(classlist, 1), name)]
              for key, value in classes:
                  contents.append(self.document(value, key, name))
              result = result + self.section('CLASSES', join(contents, '\n'))
  
          if funcs:
              contents = []
              for key, value in funcs:
                  contents.append(self.document(value, key, name))
              result = result + self.section('FUNCTIONS', join(contents, '\n'))
  
          if data:
              contents = []
              for key, value in data:
                  contents.append(self.docother(value, key, name, maxlen=70))
              result = result + self.section('DATA', join(contents, '\n'))
  
          if hasattr(object, '__version__'):
              version = str(object.__version__)
              if version[:11] == '$' + 'Revision: ' and version[-1:] == '$':
                  version = strip(version[11:-1])
              result = result + self.section('VERSION', version)
          if hasattr(object, '__date__'):
              result = result + self.section('DATE', str(object.__date__))
          if hasattr(object, '__author__'):
              result = result + self.section('AUTHOR', str(object.__author__))
          if hasattr(object, '__credits__'):
              result = result + self.section('CREDITS', str(object.__credits__))
          return result
  
      def docclass(self, object, name=None, mod=None):
          """Produce text documentation for a given class object."""
          realname = object.__name__
          name = name or realname
          bases = object.__bases__
  
          def makename(c, m=object.__module__):
              return classname(c, m)
  
          if name == realname:
              title = 'class ' + self.bold(realname)
          else:
              title = self.bold(name) + ' = class ' + realname
          if bases:
              parents = map(makename, bases)
              title = title + '(%s)' % join(parents, ', ')
  
          doc = getdoc(object)
          contents = doc and [doc + '\n'] or []
          push = contents.append
  
          # List the mro, if non-trivial.
          mro = deque(inspect.getmro(object))
          if len(mro) > 2:
              push("Method resolution order:")
              for base in mro:
                  push('    ' + makename(base))
              push('')
  
          # Cute little class to pump out a horizontal rule between sections.
          class HorizontalRule:
              def __init__(self):
                  self.needone = 0
              def maybe(self):
                  if self.needone:
                      push('-' * 70)
                  self.needone = 1
          hr = HorizontalRule()
  
          def spill(msg, attrs, predicate):
              ok, attrs = _split_list(attrs, predicate)
              if ok:
                  hr.maybe()
                  push(msg)
                  for name, kind, homecls, value in ok:
                      push(self.document(getattr(object, name),
                                         name, mod, object))
              return attrs
  
          def spilldescriptors(msg, attrs, predicate):
              ok, attrs = _split_list(attrs, predicate)
              if ok:
                  hr.maybe()
                  push(msg)
                  for name, kind, homecls, value in ok:
                      push(self._docdescriptor(name, value, mod))
              return attrs
  
          def spilldata(msg, attrs, predicate):
              ok, attrs = _split_list(attrs, predicate)
              if ok:
                  hr.maybe()
                  push(msg)
                  for name, kind, homecls, value in ok:
                      if (hasattr(value, '__call__') or
                              inspect.isdatadescriptor(value)):
                          doc = getdoc(value)
                      else:
                          doc = None
                      push(self.docother(getattr(object, name),
                                         name, mod, maxlen=70, doc=doc) + '\n')
              return attrs
  
          attrs = filter(lambda data: visiblename(data[0]),
                         classify_class_attrs(object))
          while attrs:
              if mro:
                  thisclass = mro.popleft()
              else:
                  thisclass = attrs[0][2]
              attrs, inherited = _split_list(attrs, lambda t: t[2] is thisclass)
  
              if thisclass is __builtin__.object:
                  attrs = inherited
                  continue
              elif thisclass is object:
                  tag = "defined here"
              else:
                  tag = "inherited from %s" % classname(thisclass,
                                                        object.__module__)
  
              # Sort attrs by name.
              attrs.sort()
  
              # Pump out the attrs, segregated by kind.
              attrs = spill("Methods %s:\n" % tag, attrs,
                            lambda t: t[1] == 'method')
              attrs = spill("Class methods %s:\n" % tag, attrs,
                            lambda t: t[1] == 'class method')
              attrs = spill("Static methods %s:\n" % tag, attrs,
                            lambda t: t[1] == 'static method')
              attrs = spilldescriptors("Data descriptors %s:\n" % tag, attrs,
                                       lambda t: t[1] == 'data descriptor')
              attrs = spilldata("Data and other attributes %s:\n" % tag, attrs,
                                lambda t: t[1] == 'data')
              assert attrs == []
              attrs = inherited
  
          contents = '\n'.join(contents)
          if not contents:
              return title + '\n'
          return title + '\n' + self.indent(rstrip(contents), ' |  ') + '\n'
  
      def formatvalue(self, object):
          """Format an argument default value as text."""
          return '=' + self.repr(object)
  
      def docroutine(self, object, name=None, mod=None, cl=None):
          """Produce text documentation for a function or method object."""
          realname = object.__name__
          name = name or realname
          note = ''
          skipdocs = 0
          if inspect.ismethod(object):
              imclass = object.im_class
              if cl:
                  if imclass is not cl:
                      note = ' from ' + classname(imclass, mod)
              else:
                  if object.im_self is not None:
                      note = ' method of %s instance' % classname(
                          object.im_self.__class__, mod)
                  else:
                      note = ' unbound %s method' % classname(imclass,mod)
              object = object.im_func
  
          if name == realname:
              title = self.bold(realname)
          else:
              if (cl and realname in cl.__dict__ and
                  cl.__dict__[realname] is object):
                  skipdocs = 1
              title = self.bold(name) + ' = ' + realname
          if inspect.isfunction(object):
              args, varargs, varkw, defaults = inspect.getargspec(object)
              argspec = inspect.formatargspec(
                  args, varargs, varkw, defaults, formatvalue=self.formatvalue)
              if realname == '<lambda>':
                  title = self.bold(name) + ' lambda '
                  argspec = argspec[1:-1] # remove parentheses
          else:
              argspec = '(...)'
          decl = title + argspec + note
  
          if skipdocs:
              return decl + '\n'
          else:
              doc = getdoc(object) or ''
              return decl + '\n' + (doc and rstrip(self.indent(doc)) + '\n')
  
      def _docdescriptor(self, name, value, mod):
          results = []
          push = results.append
  
          if name:
              push(self.bold(name))
              push('\n')
          doc = getdoc(value) or ''
          if doc:
              push(self.indent(doc))
              push('\n')
          return ''.join(results)
  
      def docproperty(self, object, name=None, mod=None, cl=None):
          """Produce text documentation for a property."""
          return self._docdescriptor(name, object, mod)
  
      def docdata(self, object, name=None, mod=None, cl=None):
          """Produce text documentation for a data descriptor."""
          return self._docdescriptor(name, object, mod)
  
      def docother(self, object, name=None, mod=None, parent=None, maxlen=None, doc=None):
          """Produce text documentation for a data object."""
          repr = self.repr(object)
          if maxlen:
              line = (name and name + ' = ' or '') + repr
              chop = maxlen - len(line)
              if chop < 0: repr = repr[:chop] + '...'
          line = (name and self.bold(name) + ' = ' or '') + repr
          if doc is not None:
              line += '\n' + self.indent(str(doc))
          return line
  
  # --------------------------------------------------------- user interfaces
  
  def pager(text):
      """The first time this is called, determine what kind of pager to use."""
      global pager
      pager = getpager()
      pager(text)
  
  def getpager():
      """Decide what method to use for paging through text."""
      if type(sys.stdout) is not types.FileType:
          return plainpager
      if not sys.stdin.isatty() or not sys.stdout.isatty():
          return plainpager
      if 'PAGER' in os.environ:
          if sys.platform == 'win32': # pipes completely broken in Windows
              return lambda text: tempfilepager(plain(text), os.environ['PAGER'])
          elif os.environ.get('TERM') in ('dumb', 'emacs'):
              return lambda text: pipepager(plain(text), os.environ['PAGER'])
          else:
              return lambda text: pipepager(text, os.environ['PAGER'])
      if os.environ.get('TERM') in ('dumb', 'emacs'):
          return plainpager
      if sys.platform == 'win32' or sys.platform.startswith('os2'):
          return lambda text: tempfilepager(plain(text), 'more <')
      if hasattr(os, 'system') and os.system('(less) 2>/dev/null') == 0:
          return lambda text: pipepager(text, 'less')
  
      import tempfile
      (fd, filename) = tempfile.mkstemp()
      os.close(fd)
      try:
          if hasattr(os, 'system') and os.system('more "%s"' % filename) == 0:
              return lambda text: pipepager(text, 'more')
          else:
              return ttypager
      finally:
          os.unlink(filename)
  
  def plain(text):
      """Remove boldface formatting from text."""
      return re.sub('.\b', '', text)
  
  def pipepager(text, cmd):
      """Page through text by feeding it to another program."""
      pipe = os.popen(cmd, 'w')
      try:
          pipe.write(text)
          pipe.close()
      except IOError:
          pass # Ignore broken pipes caused by quitting the pager program.
  
  def tempfilepager(text, cmd):
      """Page through text by invoking a program on a temporary file."""
      import tempfile
      filename = tempfile.mktemp()
      file = open(filename, 'w')
      file.write(text)
      file.close()
      try:
          os.system(cmd + ' "' + filename + '"')
      finally:
          os.unlink(filename)
  
  def ttypager(text):
      """Page through text on a text terminal."""
      lines = split(plain(text), '\n')
      try:
          import tty
          fd = sys.stdin.fileno()
          old = tty.tcgetattr(fd)
          tty.setcbreak(fd)
          getchar = lambda: sys.stdin.read(1)
      except (ImportError, AttributeError):
          tty = None
          getchar = lambda: sys.stdin.readline()[:-1][:1]
  
      try:
          r = inc = os.environ.get('LINES', 25) - 1
          sys.stdout.write(join(lines[:inc], '\n') + '\n')
          while lines[r:]:
              sys.stdout.write('-- more --')
              sys.stdout.flush()
              c = getchar()
  
              if c in ('q', 'Q'):
                  sys.stdout.write('\r          \r')
                  break
              elif c in ('\r', '\n'):
                  sys.stdout.write('\r          \r' + lines[r] + '\n')
                  r = r + 1
                  continue
              if c in ('b', 'B', '\x1b'):
                  r = r - inc - inc
                  if r < 0: r = 0
              sys.stdout.write('\n' + join(lines[r:r+inc], '\n') + '\n')
              r = r + inc
  
      finally:
          if tty:
              tty.tcsetattr(fd, tty.TCSAFLUSH, old)
  
  def plainpager(text):
      """Simply print unformatted text.  This is the ultimate fallback."""
      sys.stdout.write(plain(text))
  
  def describe(thing):
      """Produce a short description of the given thing."""
      if inspect.ismodule(thing):
          if thing.__name__ in sys.builtin_module_names:
              return 'built-in module ' + thing.__name__
          if hasattr(thing, '__path__'):
              return 'package ' + thing.__name__
          else:
              return 'module ' + thing.__name__
      if inspect.isbuiltin(thing):
          return 'built-in function ' + thing.__name__
      if inspect.isgetsetdescriptor(thing):
          return 'getset descriptor %s.%s.%s' % (
              thing.__objclass__.__module__, thing.__objclass__.__name__,
              thing.__name__)
      if inspect.ismemberdescriptor(thing):
          return 'member descriptor %s.%s.%s' % (
              thing.__objclass__.__module__, thing.__objclass__.__name__,
              thing.__name__)
      if inspect.isclass(thing):
          return 'class ' + thing.__name__
      if inspect.isfunction(thing):
          return 'function ' + thing.__name__
      if inspect.ismethod(thing):
          return 'method ' + thing.__name__
      if type(thing) is types.InstanceType:
          return 'instance of ' + thing.__class__.__name__
      return type(thing).__name__
  
  def locate(path, forceload=0):
      """Locate an object by name or dotted path, importing as necessary."""
      parts = [part for part in split(path, '.') if part]
      module, n = None, 0
      while n < len(parts):
          nextmodule = safeimport(join(parts[:n+1], '.'), forceload)
          if nextmodule: module, n = nextmodule, n + 1
          else: break
      if module:
          object = module
          for part in parts[n:]:
              try: object = getattr(object, part)
              except AttributeError: return None
          return object
      else:
          if hasattr(__builtin__, path):
              return getattr(__builtin__, path)
  
  # --------------------------------------- interactive interpreter interface
  
  text = TextDoc()
  html = HTMLDoc()
  
  class _OldStyleClass: pass
  _OLD_INSTANCE_TYPE = type(_OldStyleClass())
  
  def resolve(thing, forceload=0):
      """Given an object or a path to an object, get the object and its name."""
      if isinstance(thing, str):
          object = locate(thing, forceload)
          if not object:
              raise ImportError, 'no Python documentation found for %r' % thing
          return object, thing
      else:
          return thing, getattr(thing, '__name__', None)
  
  def render_doc(thing, title='Python Library Documentation: %s', forceload=0):
      """Render text documentation, given an object or a path to an object."""
      object, name = resolve(thing, forceload)
      desc = describe(object)
      module = inspect.getmodule(object)
      if name and '.' in name:
          desc += ' in ' + name[:name.rfind('.')]
      elif module and module is not object:
          desc += ' in module ' + module.__name__
      if type(object) is _OLD_INSTANCE_TYPE:
          # If the passed object is an instance of an old-style class,
          # document its available methods instead of its value.
          object = object.__class__
      elif not (inspect.ismodule(object) or
                inspect.isclass(object) or
                inspect.isroutine(object) or
                inspect.isgetsetdescriptor(object) or
                inspect.ismemberdescriptor(object) or
                isinstance(object, property)):
          # If the passed object is a piece of data or an instance,
          # document its available methods instead of its value.
          object = type(object)
          desc += ' object'
      return title % desc + '\n\n' + text.document(object, name)
  
  def doc(thing, title='Python Library Documentation: %s', forceload=0):
      """Display text documentation, given an object or a path to an object."""
      try:
          pager(render_doc(thing, title, forceload))
      except (ImportError, ErrorDuringImport), value:
          print value
  
  def writedoc(thing, forceload=0):
      """Write HTML documentation to a file in the current directory."""
      try:
          object, name = resolve(thing, forceload)
          page = html.page(describe(object), html.document(object, name))
          file = open(name + '.html', 'w')
          file.write(page)
          file.close()
          print 'wrote', name + '.html'
      except (ImportError, ErrorDuringImport), value:
          print value
  
  def writedocs(dir, pkgpath='', done=None):
      """Write out HTML documentation for all modules in a directory tree."""
      if done is None: done = {}
      for importer, modname, ispkg in pkgutil.walk_packages([dir], pkgpath):
          writedoc(modname)
      return
  
  class Helper:
  
      # These dictionaries map a topic name to either an alias, or a tuple
      # (label, seealso-items).  The "label" is the label of the corresponding
      # section in the .rst file under Doc/ and an index into the dictionary
      # in pydoc_topics.py.
      #
      # CAUTION: if you change one of these dictionaries, be sure to adapt the
      #          list of needed labels in Doc/tools/sphinxext/pyspecific.py and
      #          regenerate the pydoc_topics.py file by running
      #              make pydoc-topics
      #          in Doc/ and copying the output file into the Lib/ directory.
  
      keywords = {
          'and': 'BOOLEAN',
          'as': 'with',
          'assert': ('assert', ''),
          'break': ('break', 'while for'),
          'class': ('class', 'CLASSES SPECIALMETHODS'),
          'continue': ('continue', 'while for'),
          'def': ('function', ''),
          'del': ('del', 'BASICMETHODS'),
          'elif': 'if',
          'else': ('else', 'while for'),
          'except': 'try',
          'exec': ('exec', ''),
          'finally': 'try',
          'for': ('for', 'break continue while'),
          'from': 'import',
          'global': ('global', 'NAMESPACES'),
          'if': ('if', 'TRUTHVALUE'),
          'import': ('import', 'MODULES'),
          'in': ('in', 'SEQUENCEMETHODS2'),
          'is': 'COMPARISON',
          'lambda': ('lambda', 'FUNCTIONS'),
          'not': 'BOOLEAN',
          'or': 'BOOLEAN',
          'pass': ('pass', ''),
          'print': ('print', ''),
          'raise': ('raise', 'EXCEPTIONS'),
          'return': ('return', 'FUNCTIONS'),
          'try': ('try', 'EXCEPTIONS'),
          'while': ('while', 'break continue if TRUTHVALUE'),
          'with': ('with', 'CONTEXTMANAGERS EXCEPTIONS yield'),
          'yield': ('yield', ''),
      }
      # Either add symbols to this dictionary or to the symbols dictionary
      # directly: Whichever is easier. They are merged later.
      _symbols_inverse = {
          'STRINGS' : ("'", "'''", "r'", "u'", '"""', '"', 'r"', 'u"'),
          'OPERATORS' : ('+', '-', '*', '**', '/', '//', '%', '<<', '>>', '&',
                         '|', '^', '~', '<', '>', '<=', '>=', '==', '!=', '<>'),
          'COMPARISON' : ('<', '>', '<=', '>=', '==', '!=', '<>'),
          'UNARY' : ('-', '~'),
          'AUGMENTEDASSIGNMENT' : ('+=', '-=', '*=', '/=', '%=', '&=', '|=',
                                  '^=', '<<=', '>>=', '**=', '//='),
          'BITWISE' : ('<<', '>>', '&', '|', '^', '~'),
          'COMPLEX' : ('j', 'J')
      }
      symbols = {
          '%': 'OPERATORS FORMATTING',
          '**': 'POWER',
          ',': 'TUPLES LISTS FUNCTIONS',
          '.': 'ATTRIBUTES FLOAT MODULES OBJECTS',
          '...': 'ELLIPSIS',
          ':': 'SLICINGS DICTIONARYLITERALS',
          '@': 'def class',
          '\\': 'STRINGS',
          '_': 'PRIVATENAMES',
          '__': 'PRIVATENAMES SPECIALMETHODS',
          '`': 'BACKQUOTES',
          '(': 'TUPLES FUNCTIONS CALLS',
          ')': 'TUPLES FUNCTIONS CALLS',
          '[': 'LISTS SUBSCRIPTS SLICINGS',
          ']': 'LISTS SUBSCRIPTS SLICINGS'
      }
      for topic, symbols_ in _symbols_inverse.iteritems():
          for symbol in symbols_:
              topics = symbols.get(symbol, topic)
              if topic not in topics:
                  topics = topics + ' ' + topic
              symbols[symbol] = topics
  
      topics = {
          'TYPES': ('types', 'STRINGS UNICODE NUMBERS SEQUENCES MAPPINGS '
                    'FUNCTIONS CLASSES MODULES FILES inspect'),
          'STRINGS': ('strings', 'str UNICODE SEQUENCES STRINGMETHODS FORMATTING '
                      'TYPES'),
          'STRINGMETHODS': ('string-methods', 'STRINGS FORMATTING'),
          'FORMATTING': ('formatstrings', 'OPERATORS'),
          'UNICODE': ('strings', 'encodings unicode SEQUENCES STRINGMETHODS '
                      'FORMATTING TYPES'),
          'NUMBERS': ('numbers', 'INTEGER FLOAT COMPLEX TYPES'),
          'INTEGER': ('integers', 'int range'),
          'FLOAT': ('floating', 'float math'),
          'COMPLEX': ('imaginary', 'complex cmath'),
          'SEQUENCES': ('typesseq', 'STRINGMETHODS FORMATTING xrange LISTS'),
          'MAPPINGS': 'DICTIONARIES',
          'FUNCTIONS': ('typesfunctions', 'def TYPES'),
          'METHODS': ('typesmethods', 'class def CLASSES TYPES'),
          'CODEOBJECTS': ('bltin-code-objects', 'compile FUNCTIONS TYPES'),
          'TYPEOBJECTS': ('bltin-type-objects', 'types TYPES'),
          'FRAMEOBJECTS': 'TYPES',
          'TRACEBACKS': 'TYPES',
          'NONE': ('bltin-null-object', ''),
          'ELLIPSIS': ('bltin-ellipsis-object', 'SLICINGS'),
          'FILES': ('bltin-file-objects', ''),
          'SPECIALATTRIBUTES': ('specialattrs', ''),
          'CLASSES': ('types', 'class SPECIALMETHODS PRIVATENAMES'),
          'MODULES': ('typesmodules', 'import'),
          'PACKAGES': 'import',
          'EXPRESSIONS': ('operator-summary', 'lambda or and not in is BOOLEAN '
                          'COMPARISON BITWISE SHIFTING BINARY FORMATTING POWER '
                          'UNARY ATTRIBUTES SUBSCRIPTS SLICINGS CALLS TUPLES '
                          'LISTS DICTIONARIES BACKQUOTES'),
          'OPERATORS': 'EXPRESSIONS',
          'PRECEDENCE': 'EXPRESSIONS',
          'OBJECTS': ('objects', 'TYPES'),
          'SPECIALMETHODS': ('specialnames', 'BASICMETHODS ATTRIBUTEMETHODS '
                             'CALLABLEMETHODS SEQUENCEMETHODS1 MAPPINGMETHODS '
                             'SEQUENCEMETHODS2 NUMBERMETHODS CLASSES'),
          'BASICMETHODS': ('customization', 'cmp hash repr str SPECIALMETHODS'),
          'ATTRIBUTEMETHODS': ('attribute-access', 'ATTRIBUTES SPECIALMETHODS'),
          'CALLABLEMETHODS': ('callable-types', 'CALLS SPECIALMETHODS'),
          'SEQUENCEMETHODS1': ('sequence-types', 'SEQUENCES SEQUENCEMETHODS2 '
                               'SPECIALMETHODS'),
          'SEQUENCEMETHODS2': ('sequence-methods', 'SEQUENCES SEQUENCEMETHODS1 '
                               'SPECIALMETHODS'),
          'MAPPINGMETHODS': ('sequence-types', 'MAPPINGS SPECIALMETHODS'),
          'NUMBERMETHODS': ('numeric-types', 'NUMBERS AUGMENTEDASSIGNMENT '
                            'SPECIALMETHODS'),
          'EXECUTION': ('execmodel', 'NAMESPACES DYNAMICFEATURES EXCEPTIONS'),
          'NAMESPACES': ('naming', 'global ASSIGNMENT DELETION DYNAMICFEATURES'),
          'DYNAMICFEATURES': ('dynamic-features', ''),
          'SCOPING': 'NAMESPACES',
          'FRAMES': 'NAMESPACES',
          'EXCEPTIONS': ('exceptions', 'try except finally raise'),
          'COERCIONS': ('coercion-rules','CONVERSIONS'),
          'CONVERSIONS': ('conversions', 'COERCIONS'),
          'IDENTIFIERS': ('identifiers', 'keywords SPECIALIDENTIFIERS'),
          'SPECIALIDENTIFIERS': ('id-classes', ''),
          'PRIVATENAMES': ('atom-identifiers', ''),
          'LITERALS': ('atom-literals', 'STRINGS BACKQUOTES NUMBERS '
                       'TUPLELITERALS LISTLITERALS DICTIONARYLITERALS'),
          'TUPLES': 'SEQUENCES',
          'TUPLELITERALS': ('exprlists', 'TUPLES LITERALS'),
          'LISTS': ('typesseq-mutable', 'LISTLITERALS'),
          'LISTLITERALS': ('lists', 'LISTS LITERALS'),
          'DICTIONARIES': ('typesmapping', 'DICTIONARYLITERALS'),
          'DICTIONARYLITERALS': ('dict', 'DICTIONARIES LITERALS'),
          'BACKQUOTES': ('string-conversions', 'repr str STRINGS LITERALS'),
          'ATTRIBUTES': ('attribute-references', 'getattr hasattr setattr '
                         'ATTRIBUTEMETHODS'),
          'SUBSCRIPTS': ('subscriptions', 'SEQUENCEMETHODS1'),
          'SLICINGS': ('slicings', 'SEQUENCEMETHODS2'),
          'CALLS': ('calls', 'EXPRESSIONS'),
          'POWER': ('power', 'EXPRESSIONS'),
          'UNARY': ('unary', 'EXPRESSIONS'),
          'BINARY': ('binary', 'EXPRESSIONS'),
          'SHIFTING': ('shifting', 'EXPRESSIONS'),
          'BITWISE': ('bitwise', 'EXPRESSIONS'),
          'COMPARISON': ('comparisons', 'EXPRESSIONS BASICMETHODS'),
          'BOOLEAN': ('booleans', 'EXPRESSIONS TRUTHVALUE'),
          'ASSERTION': 'assert',
          'ASSIGNMENT': ('assignment', 'AUGMENTEDASSIGNMENT'),
          'AUGMENTEDASSIGNMENT': ('augassign', 'NUMBERMETHODS'),
          'DELETION': 'del',
          'PRINTING': 'print',
          'RETURNING': 'return',
          'IMPORTING': 'import',
          'CONDITIONAL': 'if',
          'LOOPING': ('compound', 'for while break continue'),
          'TRUTHVALUE': ('truth', 'if while and or not BASICMETHODS'),
          'DEBUGGING': ('debugger', 'pdb'),
          'CONTEXTMANAGERS': ('context-managers', 'with'),
      }
  
      def __init__(self, input=None, output=None):
          self._input = input
          self._output = output
  
      input  = property(lambda self: self._input or sys.stdin)
      output = property(lambda self: self._output or sys.stdout)
  
      def __repr__(self):
          if inspect.stack()[1][3] == '?':
              self()
              return ''
          return '<pydoc.Helper instance>'
  
      def __call__(self, request=None):
          if request is not None:
              self.help(request)
          else:
              self.intro()
              self.interact()
              self.output.write('''
  You are now leaving help and returning to the Python interpreter.
  If you want to ask for help on a particular object directly from the
  interpreter, you can type "help(object)".  Executing "help('string')"
  has the same effect as typing a particular string at the help> prompt.
  ''')
  
      def interact(self):
          self.output.write('\n')
          while True:
              try:
                  request = self.getline('help> ')
                  if not request: break
              except (KeyboardInterrupt, EOFError):
                  break
              request = strip(replace(request, '"', '', "'", ''))
              if lower(request) in ('q', 'quit'): break
              self.help(request)
  
      def getline(self, prompt):
          """Read one line, using raw_input when available."""
          if self.input is sys.stdin:
              return raw_input(prompt)
          else:
              self.output.write(prompt)
              self.output.flush()
              return self.input.readline()
  
      def help(self, request):
          if type(request) is type(''):
              request = request.strip()
              if request == 'help': self.intro()
              elif request == 'keywords': self.listkeywords()
              elif request == 'symbols': self.listsymbols()
              elif request == 'topics': self.listtopics()
              elif request == 'modules': self.listmodules()
              elif request[:8] == 'modules ':
                  self.listmodules(split(request)[1])
              elif request in self.symbols: self.showsymbol(request)
              elif request in self.keywords: self.showtopic(request)
              elif request in self.topics: self.showtopic(request)
              elif request: doc(request, 'Help on %s:')
          elif isinstance(request, Helper): self()
          else: doc(request, 'Help on %s:')
          self.output.write('\n')
  
      def intro(self):
          self.output.write('''
  Welcome to Python %s!  This is the online help utility.
  
  If this is your first time using Python, you should definitely check out
  the tutorial on the Internet at http://docs.python.org/tutorial/.
  
  Enter the name of any module, keyword, or topic to get help on writing
  Python programs and using Python modules.  To quit this help utility and
  return to the interpreter, just type "quit".
  
  To get a list of available modules, keywords, or topics, type "modules",
  "keywords", or "topics".  Each module also comes with a one-line summary
  of what it does; to list the modules whose summaries contain a given word
  such as "spam", type "modules spam".
  ''' % sys.version[:3])
  
      def list(self, items, columns=4, width=80):
          items = items[:]
          items.sort()
          colw = width / columns
          rows = (len(items) + columns - 1) / columns
          for row in range(rows):
              for col in range(columns):
                  i = col * rows + row
                  if i < len(items):
                      self.output.write(items[i])
                      if col < columns - 1:
                          self.output.write(' ' + ' ' * (colw-1 - len(items[i])))
              self.output.write('\n')
  
      def listkeywords(self):
          self.output.write('''
  Here is a list of the Python keywords.  Enter any keyword to get more help.
  
  ''')
          self.list(self.keywords.keys())
  
      def listsymbols(self):
          self.output.write('''
  Here is a list of the punctuation symbols which Python assigns special meaning
  to. Enter any symbol to get more help.
  
  ''')
          self.list(self.symbols.keys())
  
      def listtopics(self):
          self.output.write('''
  Here is a list of available topics.  Enter any topic name to get more help.
  
  ''')
          self.list(self.topics.keys())
  
      def showtopic(self, topic, more_xrefs=''):
          try:
              import pydoc_topics
          except ImportError:
              self.output.write('''
  Sorry, topic and keyword documentation is not available because the
  module "pydoc_topics" could not be found.
  ''')
              return
          target = self.topics.get(topic, self.keywords.get(topic))
          if not target:
              self.output.write('no documentation found for %s\n' % repr(topic))
              return
          if type(target) is type(''):
              return self.showtopic(target, more_xrefs)
  
          label, xrefs = target
          try:
              doc = pydoc_topics.topics[label]
          except KeyError:
              self.output.write('no documentation found for %s\n' % repr(topic))
              return
          pager(strip(doc) + '\n')
          if more_xrefs:
              xrefs = (xrefs or '') + ' ' + more_xrefs
          if xrefs:
              import StringIO, formatter
              buffer = StringIO.StringIO()
              formatter.DumbWriter(buffer).send_flowing_data(
                  'Related help topics: ' + join(split(xrefs), ', ') + '\n')
              self.output.write('\n%s\n' % buffer.getvalue())
  
      def showsymbol(self, symbol):
          target = self.symbols[symbol]
          topic, _, xrefs = target.partition(' ')
          self.showtopic(topic, xrefs)
  
      def listmodules(self, key=''):
          if key:
              self.output.write('''
  Here is a list of matching modules.  Enter any module name to get more help.
  
  ''')
              apropos(key)
          else:
              self.output.write('''
  Please wait a moment while I gather a list of all available modules...
  
  ''')
              modules = {}
              def callback(path, modname, desc, modules=modules):
                  if modname and modname[-9:] == '.__init__':
                      modname = modname[:-9] + ' (package)'
                  if find(modname, '.') < 0:
                      modules[modname] = 1
              def onerror(modname):
                  callback(None, modname, None)
              ModuleScanner().run(callback, onerror=onerror)
              self.list(modules.keys())
              self.output.write('''
  Enter any module name to get more help.  Or, type "modules spam" to search
  for modules whose descriptions contain the word "spam".
  ''')
  
  help = Helper()
  
  class Scanner:
      """A generic tree iterator."""
      def __init__(self, roots, children, descendp):
          self.roots = roots[:]
          self.state = []
          self.children = children
          self.descendp = descendp
  
      def next(self):
          if not self.state:
              if not self.roots:
                  return None
              root = self.roots.pop(0)
              self.state = [(root, self.children(root))]
          node, children = self.state[-1]
          if not children:
              self.state.pop()
              return self.next()
          child = children.pop(0)
          if self.descendp(child):
              self.state.append((child, self.children(child)))
          return child
  
  
  class ModuleScanner:
      """An interruptible scanner that searches module synopses."""
  
      def run(self, callback, key=None, completer=None, onerror=None):
          if key: key = lower(key)
          self.quit = False
          seen = {}
  
          for modname in sys.builtin_module_names:
              if modname != '__main__':
                  seen[modname] = 1
                  if key is None:
                      callback(None, modname, '')
                  else:
                      desc = split(__import__(modname).__doc__ or '', '\n')[0]
                      if find(lower(modname + ' - ' + desc), key) >= 0:
                          callback(None, modname, desc)
  
          for importer, modname, ispkg in pkgutil.walk_packages(onerror=onerror):
              if self.quit:
                  break
              if key is None:
                  callback(None, modname, '')
              else:
                  loader = importer.find_module(modname)
                  if hasattr(loader,'get_source'):
                      import StringIO
                      desc = source_synopsis(
                          StringIO.StringIO(loader.get_source(modname))
                      ) or ''
                      if hasattr(loader,'get_filename'):
                          path = loader.get_filename(modname)
                      else:
                          path = None
                  else:
                      module = loader.load_module(modname)
                      desc = (module.__doc__ or '').splitlines()[0]
                      path = getattr(module,'__file__',None)
                  if find(lower(modname + ' - ' + desc), key) >= 0:
                      callback(path, modname, desc)
  
          if completer:
              completer()
  
  def apropos(key):
      """Print all the one-line module summaries that contain a substring."""
      def callback(path, modname, desc):
          if modname[-9:] == '.__init__':
              modname = modname[:-9] + ' (package)'
          print modname, desc and '- ' + desc
      def onerror(modname):
          # Ignore non-ImportError exceptions raised whilst trying to
          # import modules
          pass
      try: import warnings
      except ImportError: pass
      else: warnings.filterwarnings('ignore') # ignore problems during import
      ModuleScanner().run(callback, key, onerror=onerror)
  
  # --------------------------------------------------- web browser interface
  
  def serve(port, callback=None, completer=None):
      import BaseHTTPServer, mimetools, select
  
      # Patch up mimetools.Message so it doesn't break if rfc822 is reloaded.
      class Message(mimetools.Message):
          def __init__(self, fp, seekable=1):
              Message = self.__class__
              Message.__bases__[0].__bases__[0].__init__(self, fp, seekable)
              self.encodingheader = self.getheader('content-transfer-encoding')
              self.typeheader = self.getheader('content-type')
              self.parsetype()
              self.parseplist()
  
      class DocHandler(BaseHTTPServer.BaseHTTPRequestHandler):
          def send_document(self, title, contents):
              try:
                  self.send_response(200)
                  self.send_header('Content-Type', 'text/html')
                  self.end_headers()
                  self.wfile.write(html.page(title, contents))
              except IOError: pass
  
          def do_GET(self):
              path = self.path
              if path[-5:] == '.html': path = path[:-5]
              if path[:1] == '/': path = path[1:]
              if path and path != '.':
                  try:
                      obj = locate(path, forceload=1)
                  except ErrorDuringImport, value:
                      self.send_document(path, html.escape(str(value)))
                      return
                  if obj:
                      self.send_document(describe(obj), html.document(obj, path))
                  else:
                      self.send_document(path,
  'no Python documentation found for %s' % repr(path))
              else:
                  heading = html.heading(
  '<big><big><strong>Python: Index of Modules</strong></big></big>',
  '#ffffff', '#7799ee')
                  def bltinlink(name):
                      return '<a href="%s.html">%s</a>' % (name, name)
                  names = filter(lambda x: x != '__main__',
                                 sys.builtin_module_names)
                  contents = html.multicolumn(names, bltinlink)
                  indices = ['<p>' + html.bigsection(
                      'Built-in Modules', '#ffffff', '#ee77aa', contents)]
  
                  seen = {}
                  for dir in sys.path:
                      indices.append(html.index(dir, seen))
                  contents = heading + join(indices) + '''<p align=right>
  <font color="#909090" face="helvetica, arial"><strong>
  pydoc</strong> by Ka-Ping Yee &lt;ping@lfw.org&gt;</font>'''
                  self.send_document('Index of Modules', contents)
  
          def log_message(self, *args): pass
  
      class DocServer(BaseHTTPServer.HTTPServer):
          def __init__(self, port, callback):
              host = (sys.platform == 'mac') and '127.0.0.1' or 'localhost'
              self.address = ('', port)
              self.url = 'http://%s:%d/' % (host, port)
              self.callback = callback
              self.base.__init__(self, self.address, self.handler)
  
          def serve_until_quit(self):
              import select
              self.quit = False
              while not self.quit:
                  rd, wr, ex = select.select([self.socket.fileno()], [], [], 1)
                  if rd: self.handle_request()
  
          def server_activate(self):
              self.base.server_activate(self)
              if self.callback: self.callback(self)
  
      DocServer.base = BaseHTTPServer.HTTPServer
      DocServer.handler = DocHandler
      DocHandler.MessageClass = Message
      try:
          try:
              DocServer(port, callback).serve_until_quit()
          except (KeyboardInterrupt, select.error):
              pass
      finally:
          if completer: completer()
  
  # ----------------------------------------------------- graphical interface
  
  def gui():
      """Graphical interface (starts web server and pops up a control window)."""
      class GUI:
          def __init__(self, window, port=7464):
              self.window = window
              self.server = None
              self.scanner = None
  
              import Tkinter
              self.server_frm = Tkinter.Frame(window)
              self.title_lbl = Tkinter.Label(self.server_frm,
                  text='Starting server...\n ')
              self.open_btn = Tkinter.Button(self.server_frm,
                  text='open browser', command=self.open, state='disabled')
              self.quit_btn = Tkinter.Button(self.server_frm,
                  text='quit serving', command=self.quit, state='disabled')
  
              self.search_frm = Tkinter.Frame(window)
              self.search_lbl = Tkinter.Label(self.search_frm, text='Search for')
              self.search_ent = Tkinter.Entry(self.search_frm)
              self.search_ent.bind('<Return>', self.search)
              self.stop_btn = Tkinter.Button(self.search_frm,
                  text='stop', pady=0, command=self.stop, state='disabled')
              if sys.platform == 'win32':
                  # Trying to hide and show this button crashes under Windows.
                  self.stop_btn.pack(side='right')
  
              self.window.title('pydoc')
              self.window.protocol('WM_DELETE_WINDOW', self.quit)
              self.title_lbl.pack(side='top', fill='x')
              self.open_btn.pack(side='left', fill='x', expand=1)
              self.quit_btn.pack(side='right', fill='x', expand=1)
              self.server_frm.pack(side='top', fill='x')
  
              self.search_lbl.pack(side='left')
              self.search_ent.pack(side='right', fill='x', expand=1)
              self.search_frm.pack(side='top', fill='x')
              self.search_ent.focus_set()
  
              font = ('helvetica', sys.platform == 'win32' and 8 or 10)
              self.result_lst = Tkinter.Listbox(window, font=font, height=6)
              self.result_lst.bind('<Button-1>', self.select)
              self.result_lst.bind('<Double-Button-1>', self.goto)
              self.result_scr = Tkinter.Scrollbar(window,
                  orient='vertical', command=self.result_lst.yview)
              self.result_lst.config(yscrollcommand=self.result_scr.set)
  
              self.result_frm = Tkinter.Frame(window)
              self.goto_btn = Tkinter.Button(self.result_frm,
                  text='go to selected', command=self.goto)
              self.hide_btn = Tkinter.Button(self.result_frm,
                  text='hide results', command=self.hide)
              self.goto_btn.pack(side='left', fill='x', expand=1)
              self.hide_btn.pack(side='right', fill='x', expand=1)
  
              self.window.update()
              self.minwidth = self.window.winfo_width()
              self.minheight = self.window.winfo_height()
              self.bigminheight = (self.server_frm.winfo_reqheight() +
                                   self.search_frm.winfo_reqheight() +
                                   self.result_lst.winfo_reqheight() +
                                   self.result_frm.winfo_reqheight())
              self.bigwidth, self.bigheight = self.minwidth, self.bigminheight
              self.expanded = 0
              self.window.wm_geometry('%dx%d' % (self.minwidth, self.minheight))
              self.window.wm_minsize(self.minwidth, self.minheight)
              self.window.tk.willdispatch()
  
              import threading
              threading.Thread(
                  target=serve, args=(port, self.ready, self.quit)).start()
  
          def ready(self, server):
              self.server = server
              self.title_lbl.config(
                  text='Python documentation server at\n' + server.url)
              self.open_btn.config(state='normal')
              self.quit_btn.config(state='normal')
  
          def open(self, event=None, url=None):
              url = url or self.server.url
              try:
                  import webbrowser
                  webbrowser.open(url)
              except ImportError: # pre-webbrowser.py compatibility
                  if sys.platform == 'win32':
                      os.system('start "%s"' % url)
                  elif sys.platform == 'mac':
                      try: import ic
                      except ImportError: pass
                      else: ic.launchurl(url)
                  else:
                      rc = os.system('netscape -remote "openURL(%s)" &' % url)
                      if rc: os.system('netscape "%s" &' % url)
  
          def quit(self, event=None):
              if self.server:
                  self.server.quit = 1
              self.window.quit()
  
          def search(self, event=None):
              key = self.search_ent.get()
              self.stop_btn.pack(side='right')
              self.stop_btn.config(state='normal')
              self.search_lbl.config(text='Searching for "%s"...' % key)
              self.search_ent.forget()
              self.search_lbl.pack(side='left')
              self.result_lst.delete(0, 'end')
              self.goto_btn.config(state='disabled')
              self.expand()
  
              import threading
              if self.scanner:
                  self.scanner.quit = 1
              self.scanner = ModuleScanner()
              threading.Thread(target=self.scanner.run,
                               args=(self.update, key, self.done)).start()
  
          def update(self, path, modname, desc):
              if modname[-9:] == '.__init__':
                  modname = modname[:-9] + ' (package)'
              self.result_lst.insert('end',
                  modname + ' - ' + (desc or '(no description)'))
  
          def stop(self, event=None):
              if self.scanner:
                  self.scanner.quit = 1
                  self.scanner = None
  
          def done(self):
              self.scanner = None
              self.search_lbl.config(text='Search for')
              self.search_lbl.pack(side='left')
              self.search_ent.pack(side='right', fill='x', expand=1)
              if sys.platform != 'win32': self.stop_btn.forget()
              self.stop_btn.config(state='disabled')
  
          def select(self, event=None):
              self.goto_btn.config(state='normal')
  
          def goto(self, event=None):
              selection = self.result_lst.curselection()
              if selection:
                  modname = split(self.result_lst.get(selection[0]))[0]
                  self.open(url=self.server.url + modname + '.html')
  
          def collapse(self):
              if not self.expanded: return
              self.result_frm.forget()
              self.result_scr.forget()
              self.result_lst.forget()
              self.bigwidth = self.window.winfo_width()
              self.bigheight = self.window.winfo_height()
              self.window.wm_geometry('%dx%d' % (self.minwidth, self.minheight))
              self.window.wm_minsize(self.minwidth, self.minheight)
              self.expanded = 0
  
          def expand(self):
              if self.expanded: return
              self.result_frm.pack(side='bottom', fill='x')
              self.result_scr.pack(side='right', fill='y')
              self.result_lst.pack(side='top', fill='both', expand=1)
              self.window.wm_geometry('%dx%d' % (self.bigwidth, self.bigheight))
              self.window.wm_minsize(self.minwidth, self.bigminheight)
              self.expanded = 1
  
          def hide(self, event=None):
              self.stop()
              self.collapse()
  
      import Tkinter
      try:
          root = Tkinter.Tk()
          # Tk will crash if pythonw.exe has an XP .manifest
          # file and the root has is not destroyed explicitly.
          # If the problem is ever fixed in Tk, the explicit
          # destroy can go.
          try:
              gui = GUI(root)
              root.mainloop()
          finally:
              root.destroy()
      except KeyboardInterrupt:
          pass
  
  # -------------------------------------------------- command-line interface
  
  def ispath(x):
      return isinstance(x, str) and find(x, os.sep) >= 0
  
  def cli():
      """Command-line interface (looks at sys.argv to decide what to do)."""
      import getopt
      class BadUsage: pass
  
      # Scripts don't get the current directory in their path by default
      # unless they are run with the '-m' switch
      if '' not in sys.path:
          scriptdir = os.path.dirname(sys.argv[0])
          if scriptdir in sys.path:
              sys.path.remove(scriptdir)
          sys.path.insert(0, '.')
  
      try:
          opts, args = getopt.getopt(sys.argv[1:], 'gk:p:w')
          writing = 0
  
          for opt, val in opts:
              if opt == '-k':
                  apropos(val)
                  return
              if opt == '-p':
                  try:
                      port = int(val)
                  except ValueError:
                      raise BadUsage
                  def ready(server):
                      print 'pydoc server ready at %s' % server.url
                  def stopped():
                      print 'pydoc server stopped'
                  serve(port, ready, stopped)
                  return
              if opt == '-w':
                  writing = 1
  
          if not args: raise BadUsage
          for arg in args:
              if ispath(arg) and not os.path.exists(arg):
                  print 'file %r does not exist' % arg
                  break
              try:
                  if ispath(arg) and os.path.isfile(arg):
                      arg = importfile(arg)
                  if writing:
                      if ispath(arg) and os.path.isdir(arg):
                          writedocs(arg)
                      else:
                          writedoc(arg)
                  else:
                      help.help(arg)
              except ErrorDuringImport, value:
                  print value
  
      except (getopt.error, BadUsage):
          cmd = os.path.basename(sys.argv[0])
          print """pydoc - the Python documentation tool
  
  %s <name> ...
      Show text documentation on something.  <name> may be the name of a
      Python keyword, topic, function, module, or package, or a dotted
      reference to a class or function within a module or module in a
      package.  If <name> contains a '%s', it is used as the path to a
      Python source file to document. If name is 'keywords', 'topics',
      or 'modules', a listing of these things is displayed.
  
  %s -k <keyword>
      Search for a keyword in the synopsis lines of all available modules.
  
  %s -p <port>
      Start an HTTP server on the given port on the local machine.
  
  %s -w <name> ...
      Write out the HTML documentation for a module to a file in the current
      directory.  If <name> contains a '%s', it is treated as a filename; if
      it names a directory, documentation is written for all the contents.
  """ % (cmd, os.sep, cmd, cmd, cmd, os.sep)
  
  if __name__ == '__main__': cli()
  