I think I've found a bug in TextMate's regular expression format string replacement feature. Try this.

Target document:

=== testing == testing = testing

Find expression (regex):

^(=+)

Replace expression:

${1/=(=)?(=)?/${2:?2:${1:?1:0}}/}

Do a replace all. What I expect:

2 testing 1 testing 0 testing

What I get:

2 testing 1 testing 1 testing

In the last line, neither group 2 nor group 1 should be matched, since the initial equal-sign is supposed to scarf up the entire match. Therefore I expect the logic to be:

* group 2 failed, so use its "else" alternative, which is the test for group 1

* group 1 failed, so use its "else" alternative, which is the value "0"

But try as I may, I cannot make "0" appear in the document. That is the proposed bug. It is as if group 1 is thought to be _always_ satisfied, which should not be the case.

Of course, feel free to prove me wrong by fixing my find/replace expressions, thus doing my homework for me. :) m.

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