anchor.diff:  
   `graph`:: output a file in the syntax used by `graphviz`, a automatic
   graph layout tool.  Use it like: +ninja -t graph _target_ | dot -Tpng
  --ograph.png /dev/stdin+ .  In the Ninja source tree, `ninja graph`
  +-ograph.png /dev/stdin+ .  In the Ninja source tree, `ninja graph.png`
   generates an image for Ninja itself.  If no target is given generate a
   graph for all root targets.
   
  
positive.code: Generating Ninja files
  ----------------------
  
  The Ninja distribution includes a tiny (<100 line) Python module to
  facilitate generating Ninja files.  It allows you to make Python calls
  like `ninja.rule(name='foo', command='bar', depfile='$out.d')` and
  it will generate the appropriate syntax.
  
  Integration with other build systems
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  
  *gyp*. http://gyp.googlecode.com[gyp, the system used to generate build
  files for the Chromium browser] can generate ninja files for Linux.
  See http://code.google.com/p/chromium/wiki/NinjaBuild[the Chromium
  Ninja documentation] for details.
  
  *CMake*.  Various people have worked on generating Ninja files from
  CMake.  Currently, it sounds like
  https://github.com/pcc/CMake/tree/ninja-generator[pcc's branch] is the
  one to try.
  
  *Autotools*.  In theory, you could coax Automake into producing
  .ninja files as well, but I haven't tried it.  It may very well be the
  case that most projects use too much Makefile syntax in their `.am`
  files for this to work.
  
  Extra tools
  -----------
  
negative.code: are the resulting binary and this manual.
  
  
  Writing .ninja files
  --------------------
  Here's a basic `.ninja` file that demonstrates most of the syntax.
  It will be used as an example for the following sections.
  
  