 
   # Compile.
   if not helpers.isCoffee(mainModule.filename) or require.extensions
-    mainModule._compile compile(code, options), mainModule.filename
+    answer = compile(code, options)
+    # Attach sourceMap object to mainModule._sourceMaps[options.filename] so that
+    # it is accessible by Error.prepareStackTrace.
+    do patchStackTrace
+    mainModule._sourceMaps[mainModule.filename] = answer.sourceMap
+    mainModule._compile answer.js, mainModule.filename
   else
     mainModule._compile code, mainModule.filename
 

# setting `__filename`, `__dirname`, and relative `require()`.
exports.run = (code, options = {}) ->
  mainModule = require.main

  # Set the filename.
  mainModule.filename = process.argv[1] =
      if options.filename then fs.realpathSync(options.filename) else '.'

  # data for this token. Unfortunately, Jison seems to send an outdated `loc`
  # (from the previous token), so we take the location information directly
  # from the lexer.
  helpers.throwSyntaxError message, parser.lexer.yylloc

# Based on [michaelficarra/CoffeeScriptRedux](http://goo.gl/ZTx1p)
# NodeJS / V8 have no support for transforming positions in stack traces using
# sourceMap, so we must monkey-patch Error to display CoffeeScript source
# positions.

# Ideally, this would happen in a way that is scalable to multiple compile-to-
# JS languages trying to do the same thing in the same NodeJS process. We can
# implement it as if there were an API, and then patch in support for that
# API. The following maybe should be in its own npm module that multiple
# compilers can include.

patched = false
patchStackTrace = ->
  return if patched
  patched = true
  mainModule = require.main
  # Map of filenames -> functions that return a sourceMap string.
  mainModule._sourceMaps = {}

  # (Assigning to a property of the Module object in the normal module cache is
  # unsuitable, because node deletes those objects from the cache if an
  # exception is thrown in the module body.)

  Error.prepareStackTrace = (err, stack) ->
    sourceFiles = {}

    getSourceMapping = (filename, line, column) ->
      sourceMap = mainModule._sourceMaps[filename]
      answer = sourceMap.getSourcePosition [line, column] if sourceMap
      answer

    frames = for frame in stack
      break if frame.getFunction() is exports.run
      "  at #{formatSourcePosition frame, getSourceMapping}"

    "#{err.name}: #{err.message ? ''}\n#{frames.join '\n'}\n"

# Based on http://v8.googlecode.com/svn/branches/bleeding_edge/src/messages.js
# Modified to handle sourceMap
formatSourcePosition = (frame, getSourceMapping) ->
  fileName = undefined
  fileLocation = ''

  if frame.isNative()
    fileLocation = "native"
  else
    if frame.isEval()
      fileName = frame.getScriptNameOrSourceURL()
      fileLocation = "#{frame.getEvalOrigin()}, " unless fileName
    else
      fileName = frame.getFileName()

    fileName or= "<anonymous>"

    line = frame.getLineNumber()
    column = frame.getColumnNumber()

    # Check for a sourceMap position
    source = getSourceMapping fileName, line, column
    fileLocation =
      if source
        "#{fileName}:#{source[0]}:#{source[1]}, <js>:#{line}:#{column}"
      else
        "#{fileName}:#{line}:#{column}"


  functionName = frame.getFunctionName()
  isConstructor = frame.isConstructor()
  isMethodCall = not (frame.isToplevel() or isConstructor)

  if isMethodCall
    methodName = frame.getMethodName()
    typeName = frame.getTypeName()

    if functionName
      tp = as = ''
      if typeName and functionName.indexOf typeName
        tp = "#{typeName}."
      if methodName and functionName.indexOf(".#{methodName}") isnt functionName.length - methodName.length - 1
        as = " [as #{methodName}]"

      "#{tp}#{functionName}#{as} (#{fileLocation})"
    else
      "#{typeName}.#{methodName or '<anonymous>'} (#{fileLocation})"
  else if isConstructor
    "new #{functionName or '<anonymous>'} (#{fileLocation})"
  else if functionName
    "#{functionName} (#{fileLocation})"
  else
    fileLocation