What if #if/#endif blocks are nested ?
Yakov is correct, that nested #if/#endif blocks would cause
trouble.
My first thought at a [100% untested] solution would be
something like
:g/^\s*#endif/norm dV%
which would find all of the #endif tokens and delete their
associated blocks, exploiting Vim's ability to use "%" to
match #if/#else/#endif blocks. However, funky behaviors
emerge if you have an #else block, and you want some of it
in to remain behind:
#if COWS_ROLLERSKATE
foo = "limbo, limbo";
#else
foo = "mu"
#endif
With my suggestion, you would delete the whole thing, and it
would look like "foo" never gets set. It also nukes *all*
the if/endif blocks, not just select ones (such as if you
only wanted to nuke the "#if COWS_ROLLERSKATE" blocks, but
not "#if POPE_CATHOLIC" blocks)
If you don't have #else clauses, you might be able to solve
that 2nd problem with something like
:g/^\s*#if COWS_ROLLERSKATE/norm dV%
Otherwise, you'd have to do some funky testing, along the
lines of (again, 100% untested)
:g/^\s*#if COWS/exec("norm %")| exec('norm
'.(getline(".")=~'^\s*#else'?'%':'').'dV%')
which should check if, after using "%", you landed on an
#else line, in which case it adds an extra "%" to go to the
"#endif" line before deleteing back to the original. All
sorts of odd cases occur with nesting and #else blocks, so
you'd have to tinker to get the desired behavior.
-tim
