Here's a list of some of haXe features. Don't be afraid if it's too much long, you don't need to learn or use everything to get started with haXe.

Supported Platforms

• Can compile to Javascript by generating a single .js file
• Can compile to Flash 6-8 by generating a single .swf file
• Can compile to Flash 9 / Tamarin by generating a single .swf file
  • generate optimized integer arithmetic
  • autocast when reading typed arrays
• Can compile to NekoVM by generating a single .n bytecode file
  • can be run from the commandline
  • can be run on Apache Web server (with mod_neko)
• Can compile to AS3 source code
• Can compile to PHP

Compiler Features

• Debug compilation mode (enables call stack for JS and Flash 6-8)
• trace and file position support
• In-line Methods and Variables
• Runtime Type Information
• Optimized Generics (for Flash9)
• External File Resources
• Conditional Compilation
• Generate documentation and types to XML format

Libraries and Tools

• Firebug support
• Cross-platform XML support
• Cross-platform serialization to web-compatible format
• Cross-platform communications with haXe Remoting
• Build Flash Desktop Applications with ScreenweaverHX

Language Features

• Strongly Typed Language
• First-class methods and functions (closures)
• Regular Expressions
• High Level Type System including :
  • classes and interfaces
  • enums
  • function-types
  • anonymous types (structures)
  • dynamics
• Enums
  • optional constructor parameters (à la ML)
  • type parameters (polymorphism)
• Complete type inference : you don't need to type your local variables
• Type parameters (generics) with optional constraints
• Module system : packages + private definitions
• Structural Subtyping (duck typing) using type inference and anonymous types
• Polymorphic methods