If you are looking for an IDE to write Haxe code, the following options are available :
There are a great number of IDEs and editors that support Haxe:

• FlashDevelop 4 is the state of the art IDE for Haxe on Windows, offering code completion, a Flash debugger, and project templates for all targets, including NME. Read more here

• FDT 5 includes support for Haxe, and it runs on PC, Mac and Linux. It is a commercial product, with a free edition, based on Eclipse with many enterprise features.

• Textmate is used by a lot of Mac users. Textmate supports a lot of features for coding in Haxe. Read more about it here. Windows users can use E-TextEditor using the same bundle.

• Sublime Text 2 is the rising star of the code editors. Similar to TextMate but crossplatform, it is highly extensible and already has a great ecosystem of plugins, including one for haxe.

• Eclihx plug-in extends Eclipse with Haxe development support. Latest release contains autocompletion, templates, quick navigation to compile errors, configurable builds and other features. Project is open-source and cross-platform.

• But that's just the start. From textmode editors like Emacs or Vim to impressive IDEs like Eclipse here is a list of editors and how the support Haxe.

Plugins and Addons for IDEs and Editors to enable Haxe

• Boxer Editor
• Eclipse
• EditPlus
• Editra
• Emacs
• Espresso ide
• E-Texteditor
• fdt
• Fraise Editor
• Geany
• Gedit
• FlashDevelop
• Intelij
• jEdit
• Kate
• Kdevelop (nix)
• Komodo
• Konqueror (nix)
• MonoDevelop
• Notepad++
• Pacu
• SciTE
• Sublime Text 2
• Sugar-hx TextMate bundle
• TextMate (mac)
• Ultraedit (win, nix)
• Vim
• www.activestate.com
• Xcode (mac)