From: Bakul Shah <bakul@iitbombay.org>
To: Will Senn <will.senn@gmail.com>
Cc: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] Regular Expressions
Date: Fri, 31 Jul 2020 17:01:56 -0700 [thread overview]
Message-ID: <402F66B1-12C1-4FED-89FD-38AB99D919B4@iitbombay.org> (raw)
In-Reply-To: <6e9ca056-dfb0-376d-effd-e41c9ed3ef2a@gmail.com>
On Jul 31, 2020, at 3:57 PM, Will Senn <will.senn@gmail.com> wrote:
>
> I've always been intrigued with regexes. When I was first exposed to them, I was mystified and lost in the greediness of matches. Now, I use them regularly, but still have trouble using them. I think it is because I don't really understand how they work.
> ...
> 1. What's the provenance of regex in unix (when did it appear, in what form, etc)?
> 2. What are the 'best' implementations throughout unix (keep it pre 1980s)?
> 3. What are some of the milestones along the way (major changes, forks, disagreements)?
> 4. Where, in the source, or in a paper, would you point someone to wanting to better understand the mechanics of regex?
Start here: https://en.wikipedia.org/wiki/Thompson%27s_construction
[I learned about regular expressions in an automata theory class,
before I knew anything about Unix. What helped me was learning
about finite state machines. You won't need more than paper and
pencil to construct one. Reading source code would make more
sense once you grasp how to construct a FSM corresponding to a RE.]
next prev parent reply other threads:[~2020-08-01 0:03 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-31 22:57 Will Senn
2020-08-01 0:01 ` Bakul Shah [this message]
2020-08-01 0:36 ` Rob Pike
2020-08-01 0:53 ` John P. Linderman
2020-08-01 1:31 ` Bakul Shah
2020-08-01 1:39 ` Larry McVoy
2020-08-01 2:33 ` Will Senn
2020-08-01 2:50 ` Rich Morin
2020-08-01 3:01 ` Larry McVoy
2020-08-01 3:07 ` Will Senn
2020-08-01 4:31 ` Earl Baugh
2020-08-01 4:53 ` ron minnich
2020-08-01 5:48 ` Andrew Hume
2020-08-01 13:31 ` Richard Salz
2020-08-01 13:43 ` Andrew Hume
2020-08-02 0:45 ` Christopher Browne
2020-08-09 1:00 ` Dave Horsfall
2020-08-09 1:15 ` Nelson H. F. Beebe
2020-08-09 23:53 ` Dave Horsfall
2020-08-10 1:38 ` John Cowan
2020-08-01 0:00 Noel Chiappa
2020-08-01 21:12 Doug McIlroy
2020-08-09 23:44 ` Dave Horsfall
2020-08-10 0:50 ` Rob Pike
2020-08-02 4:59 Rudi Blom
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