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tom-lord/Irregular expressions

Created March 19, 2015 22:47
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Examples of regex patterns that are not truly "regular"
Raw
Irregular expressions
/\bword\b/ # How does "\b" know whether it lies on a word boundary?
/line1\n^line2/ # How does "^" know whether it lies at the start of a line?
/irregular (?=expression)/ # Or in general, how can any "look-ahead"/"look-behind" be regular?
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