This falls into the general class of "I'm using a regex, but my expression is starting to look like noise." The fastest solution in this case is use the x modifier since you don't have any whitespace in your expression: 
s/ \) ([^()]+) \(
 /  ]    $1     [
 /xg;

[download]
That's your original expression with extra whitespace.

I personally don't see the value in reducing your character count by 2 by avoiding the backslashes in the first place, but this type of process is always susceptible to Leaning_toothpick_syndrome. If I'm doing something like this, with potential nesting and the like, I always build a tree using tokens. My experience has generally shown that in these scenarios the fast solution is never actually fast.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: $1[ by kennethk
in thread $1[ by rsFalse

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