Why can't Regular Expressions use keywords instead of characters?

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甜味超标
甜味超标 2021-02-20 06:46

Okay, I barely understand RegEx basics, but why couldn\'t they design it to use keywords (like SQL) instead of some cryptic wildcard characters and symbols?

Is it for pe

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  •  深忆病人
    2021-02-20 07:34

    This is much earlier than PERL. The Wikipedia entry on Regular Expressions attributes the first implementations of regular expressions to Ken Thompson of UNIX fame, who implemented them in the QED and then the ed editor. I guess that the commands had short names for performance reasons, but much before being client-side. Mastering Regular Expressions is a great book about regular expressions, which offers the option to annotate a regular expression (with the /x flag) to make it easier to read and understand.

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