Parsers can't do lookbehind, not to mention recursive lookbehind. You're straying way off your point (that this is a parser problem, not a regexp problem) by saying variable-length lookbehind is required.

Besides, you said "The recognition of escaped escapes is a naturally recursive problem." There's nothing recursive about "Count the number of slashes leading up to the char. If the count is odd, the character is escaped. If the count is even, the character is not escaped."

In reply to Re^6: Replace only unescaped metachars by ikegami
in thread Replace only unescaped metachars by Anonymous Monk

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