help writing a command

I'm not savvy enough to see how to write a simple command for Textmate  
2, and I'm wondering if anyone can help get me started.

The command should search the current file for "ch:\d" where \d is one  
or two digits and spit that/those digits out where the cursor is.

many thanks,
Kyle

_______________________________________________
textmate mailing list
textmate@...
http://lists.macromates.com/listinfo/textmate