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Re: The poor state of documentation of pcase like things.

From: John Wiegley
Subject: Re: The poor state of documentation of pcase like things.
Date: Thu, 24 Dec 2015 09:51:08 -0800
User-agent: Gnus/5.130014 (Ma Gnus v0.14) Emacs/24.5 (darwin)

>>>>> Michael Heerdegen <address@hidden> writes:

>> I thought we were not going to mention q-patterns any more!
> I never said that. "qpattern" is a useful term when describing the `
> pattern. What I said was we should avoid the old term "upattern" for general
> type pcase patterns.

They are both terrible names. Even knowing exactly what they, they don't help
me to think about pcase.

For macros, `foo' gets evaluated, and a quoted foo doesn't. Back-quoting
reverses the idea: `foo' does not get evaluted, and a comma'd foo is.

For patterns, `foo' is computed to determine the pattern, and a quoted foo
matches exactly. Back-quoting reverse the idea: `foo' matches exactly, and a
comma'd foo is evaluated to determine its logical behavior.

John Wiegley                  GPG fingerprint = 4710 CF98 AF9B 327B B80F
http://newartisans.com                          60E1 46C4 BD1A 7AC1 4BA2

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