Guards redux

John Rose john.r.rose at
Wed Mar 10 22:05:09 UTC 2021

On Mar 10, 2021, at 8:33 AM, Remi Forax <forax at> wrote:
> As i said to Gavin, i'm not at ease with using the symbol '&' in between patterns.

Aren’t patterns inherently sequential and short-circuiting?
Or am I having a failure of imagination?  All of the pattern
syntaxes mimic expression syntaxes, but expressions are
(generally) non-short-circuiting, entailing unconditional
evaluation of subexpressions.  But every subpattern of
a pattern is conditional, which is different from expressions.
Thus, & in pattern-land is short-circuiting.

(What would a non-short-circuiting pattern look like?)

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