[TxMt] Odd behavior with "Move Selection Line Up" and "Line Down"

[Michael Henry]

Paul McCann wrote:
> While not ideal, one way to get a partial solution to this is to 
> override the "Line Up" and "Line Down" commands using macros.
>
> Sselect "Automation => Start Macro Recording" then
>
> (1) Select "Text => Move Selection => Line Up"
> (2) Hit your up arrow
>
> and finally select "Automation => Stop Macro Recording". Then use 
> "Automation =>  Save Scratch Macro..." to save this as, say, "upline" 
> with a blank scope and the same key command as "Text => Move Selection 
> => Line Up". Repeat with obvious modifications for "downline".
Thanks for the suggestion.  I agree that it's a big improvement for the 
typical use case (moving just a single line), and I may end up with this 
very work-around until the fix is made in TextMate itself.  Before 
posting, I'd created my own bundle and tried making a command that 
behaved the way I'd like, but I didn't know enough to get all the 
behavior correct.

Before purchasing TextMate (and the Macbook Pro to run it on :-)) I'd 
seen Duane Johnson's MASC hack for simultaneous caret manipulation (see 
http://blog.inquirylabs.com/my-textmate-bundle/), done solely with an 
end-user-supplied bundle.  The MASC code is a good hack, and it makes 
for a nice advertisement for the power of TextMate's extensibility.  But 
I didn't look at the actual MASC code before I delved into the bundle 
editor to hack out my own "move line up" functionality.  I started 
making a command, but I got stalled at the point where I wanted my 
command to move the caret.

I then studied the MASC bundle to see how he worked his magic.  It seems 
that Duane used snippets to position the caret.  He grabs a subset of 
the buffer, converts it to a snippet, puts in tab-stops (which give the 
caret positioning he needs), and inserts the snippet into the buffer, 
replacing the original contents.  This is a neat hack, and I may well 
use it in my attempt to make a complete temporary fix for "move line up".

But I do wonder if there is some other way to position the cursor in the 
buffer, short of inserting a snippet.  Does anyone have a better 
suggestion for bundle authors who need to process the current buffer and 
move the caret as a result?  Or is the snippet hack the best technique 
at this time?  I'm on a quest to learn how to tailor TextMate, and this 
seems like a capability I'm going to need in general.

Thanks,
Michael Henry