[TxMt] Braces inside placeholders

[Charilaos Skiadas]

I was just wondering the following was possible, and I found out it  
is, but in case other people are wondering, you can include braces in  
the snippet placeholder text, if you escape the right brace.
Why would I want to do that? Suppose I want to use nested  
placeholders, to allow for optional arguments. For instance imagine a  
snippet like:

\\foo${1:(${2:0},${3:0})}

then this will show up as \foo(0,0) with the entire (0,0)  
highlighted, so if I don't want it to be there then I can just press  
delete and continue, or if I want it I can press tab and move to  
editing each of the two zeros.

This works great in this case, but suppose I want *braces* instead of  
parentheses (as in most LaTeX commands):

\\foo${1:{${2:0},${3:0}}}

As it stands, the second to last brace is matched as closing the  
placeholder ${1, which leaves the wrong thing highlighted . The trick  
is to escape it, like so:

\\foo${1:{${2:0},${3:0}\}}

Very nifty and useful, and not documented I think. My first impulse  
was to escape the corresponding left brace as well, but it doesn't  
need (and in fact won't accept) escaping. No sure how I feel about  
that, it looks asymmetric to me. But hey, it works!

I am now very tempted to change most of the sectioning commands in  
the LaTeX bundle to make adding labels optional, and combine the  
stared versions of environment with the non-stared ones.

Haris