Ian Bicking: the old part of his blog

Re: Ofsyntaxandenvironment comment 000

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In 1.5.2, the RE module used PCRE.  In 1.6 and later, that was
replaced with a Unicode-aware engine, SRE, which was written from
scratch, using on the 1.5.2 documentation and test suite as the
specification.

(guess who wrote it? ;-)
Comment on Ofsyntaxandenvironment comment 000
by Fredrik

Comments:

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should have been "using only the"
# Fredrik