if match(getline(1,20),"^ \{0,1}\(=\{2,6}\)[^=]\+\1 *$") >= 0
The pattern used in the match() call is the same as in the
syntax highlighting script.
My guess is that it's something like an escaping problem. You're
using double-quotes which are a little more finicky about
contained-escapes. You might try
match(getline(1,20),'^ \{0,1}\(=\{2,6}\)[^=]\+\1 *$')
(using single-quotes rather than double-quotes) or
match(getline(1,20),"^ \\{0,1}\\(=\\{2,6}\\)[^=]\+\\1 *$")
(escaping your escape-characters). You can read a bit more at
:help expr-quote
:help expr-string
You can also change the \{0,1} syntax to \= for the same results.
I don't know if one is faster than another internally, or if it
even matters, but it's fewer chars to type. (":help \=")
Just a couple ideas,
-tim
