How do I use :Tabular only for delimiters after a certain pattern?

Question

How can I use the Tabular plugin to align by ";" after "//"?

With text:

Line 1 ; B // Comment 1 ; Comment 2
Line 2 C // Comment 3    ; Comment 4

After running :Tabularize /; I get:

Line 1                ; B // Comment 1 ; Comment 2
Line 2 C // Comment 3 ; Comment 4

But how do I tabularize so that I get

Line 1  ; B // Comment 1 ; Comment 2
Line 2 C   // Comment 3  ; Comment 4

Answer 1

You could use:

:Tabularize ///[^;]*\zs;

To break it down:

• // – match literal //.
• [^;]* – match zero or more characters except ;.
• \zs – set the start of the match. This is the "magic" in the regexp that makes it work; without it, the match would start at the first character (/ in this case) and Tabular would align on that, but with this it will match at the character after \zs (the desired ;).
  These sort of advanced regular expression operators can be rather hard to grok, so don't worry if you didn't quite follow that. I would encourage you to experiment. Also see :help /\zs.
• ; – match literal ;.