OPeLo

OPeLo is FREEWARE Sourcecode editor for OPL.It has Color Syntax Highlithing, Code Completion, Memberlist - CTRL J pops up a complete list with all OPL commands, User-defined Variables and Functions.

There is also parameter list help: if you define proc xxx:(a&, b&, etc.) or array&(items) the editor shows you each time you write "xxx:(" a ToolTip with the Parameter info - what this particular function expects - also in this case a&,b&,etc. The current element of the paramlist is shown bold. The array is shown with VB-like ToolTip array&( 1 of xxx ). OPeLo offers also Brace/CodeWord Matching.
Also if you have name definitions like AaBbCc and type aabbcc - you have only to press enter / go to the next line - and the editor corrects automatically the character case (makes it AaBbCc)...
Additionally you can bind opltran.exe to the editor and complie your app on the desktop, Error Messages (if any) are shown and the source code line is highlighted.