If anyone googles how to do this, here is the solution we found, it works with unsaved windows (hence the "untitled", you would have to change that depending on your use)
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In the command, execute the system comand (ours is Ruby, so backticks) `osascript switch_windows.applescript`
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Then in your Support directory, the file: switch_windows.applescript
tell application "TextMate" activate end tell tell application "System Events" set found_window to false set all_windows to every window of process "TextMate" repeat with w in all_windows if name of w contains "untitled" then set editor_window to name of w set found_window to true end if end repeat
if found_window then
tell process "TextMate" tell menu bar 1 tell menu bar item "Window" tell menu "Window" click menu item editor_window end tell end tell end tell end tell end if end tell