FlashDevelop is a free and open source code editor.  Some of its features:

  • Supports three languages: ActionScript 2, ActionScript 3 & MXML and HaXe.
  • Brilliant Actionscript Code Completion (IntelliSense) and code generators.
  • Code completion for XML, MXML and HTML
  • Code navigation (jump to declaration), just pressing F4/Shift-F4.
  • Easy integration with Flash and command line compilers, just using Ctrl+Enter to compile.
  • Integrated Project Manager to handle all the project assets, properties and files.
  • Smart project templates to quickly get started.
  • Instant swf building with MTASC or MXMLC using custom comment tag @mtasc/@mxmlc.
  • Easy to use Context API search.
  • Customized GUI for AS2API & ASDocs documentation generators.
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