Indeed. And the reason [^\1] doesn't work is... well because within a character class \1 means 1, not the contents of the capture buffer 1. Which is a long way of saying it doesn't work because it doesn't work (however plausible it may look).

In reply to Re^2: How to use a negative backreference in regex? by gone2015
in thread How to use a negative backreference in regex? by larryk

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