Ace open source code editor

If you're planning to include a live code editor in one of your projects you may have a hard time working out how to validate code within a text field and replicate formatting.

The hard work has been done for you with Ace code editor. This open source project gives you all the functionality including:

  • Syntax highlighting
  • Automatic indent and outdent
  • An optional command line
  • Handles huge documents (100,000 lines and more are no problem)
  • Fully customizable key bindings including VIM and Emacs modes
  • Themes (TextMate themes can be imported)
  • Search and replace with regular expressions
  • Highlight matching parentheses
  • Toggle between soft tabs and real tabs
  • Displays hidden characters
  • Drag and drop text using the mouse
  • Line wrapping
  • Code folding
  • Multiple selections
  • Live syntax checker (currently JavaScript/CoffeeScript/Css/XQuery)
It's so good it's used by a number of sites including the very interesting cloud coding site Cloud9:

You can view the demo at:

Or grab the source at: