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Fix alternations with empty sub-expressions with regex >= 0.2.7 #47
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With regex 0.2.7 and higher, the trick to rewrite `(a|b|)` to
`(a|b|.{0})` doesn't work anymore, it fails with this error:
> alternations cannot currently contain empty sub-expressions
So delegate it like this instead: `((?:a|b)?)`
raphlinus
approved these changes
May 1, 2018
7 tasks
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With regex 0.2.7 and higher, the trick to rewrite
(a|b|)to(a|b|.{0})doesn't work anymore, it fails with this error:So delegate it like this instead:
((?:a|b)?)