regexp.old

Henry Spencer's old regular expression library, also known as the book regex library, circa 1986.

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What it is

Henry Spencer's old regular expression library, also known as the book regex library, circa 1986.

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This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 5:04:57 PM UTC.

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Mentions over time

HN mentions by hour2 dated mentions

Observed mentions: 2017-12-05 14:37:29 UTC to 2017-12-05 15:35:00 UTC.

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Period	Start (UTC)	End (exclusive, UTC)	Mentions	Submissions	Comments
Dec 5, 14:00	2017-12-05 14:00:00 UTC	2017-12-05 15:00:00 UTC	1	0	1
Dec 5, 15:00	2017-12-05 15:00:00 UTC	2017-12-05 16:00:00 UTC	1	0	1

What Hacker News says

2 sources

rlonstein·Dec 5, 2017

> Henry Spencer's regex code: https://github.com/garyhouston/regexp.old Glad to see that come up in this thread. It was the first clearly explained regex engine for me in _Software Solutions in C_ (Schumacher D., Academic Press, 1994). I still have a copy and the original disk (and disk image). If anyone is interested I could scan that chapter tonight.

In Building a Regex Engine in Fewer Than 40 Lines of Code

microtherion·Dec 5, 2017

A bit longer than 40 lines, but back in the day, I was a big fan of the simplicity and clarity of Henry Spencer's regex code: https://github.com/garyhouston/regexp.old

In Building a Regex Engine in Fewer Than 40 Lines of Code