Hello,  I'm trying to use a regexp with look-ahead.  The search works, but clicking "replace" button does nothing.  I'm stumped.  Here's an example:

Find:  public (?=int)
Replace:  private 
Regular expression: checked
Ignore case: unchecked
Wrap around: checked

Click "find" and "public " is selected, but then clicking "replace" does nothing.  Also "replace and find" goes to the next occurrence, but does not perform the replacement.

Using Textmate 1.5.10

Thanks,
ErikN