From: Daniel Shahaf <d.s@daniel.shahaf.name>
To: zsh-workers@zsh.org
Subject: Re: Parse error (lack thereof) on incomplete loops
Date: Fri, 05 Oct 2018 13:26:32 +0000 [thread overview]
Message-ID: <1538745992.2833942.1531910952.26C1157A@webmail.messagingengine.com> (raw)
In-Reply-To: <20181005091435eucas1p26edaafb362de339b01c3cb5780fbd108~aq5QQQ6pF1496014960eucas1p2g@eucas1p2.samsung.com>
Peter Stephenson wrote on Fri, 05 Oct 2018 10:14 +0100:
> {
> while false
> true
> }
...
> Without a "do" while doesn't know where the expression ends. That's
> fundamental to how SHORT_LOOPS works and why I regard it as so
> ill-defined as to be useless in all but the simplest cases. This new
> (accidental) feature is giving it a particularly straightforward way of
> telling it where the expression ends.
>
> Anyway, I'm perfectly happy either restoring the parse error or not,
> depending on the opinions of people more likely to use or fall foul of
> this kind of syntax but I don't think the reason "it's all a bit weird"
> is good enough on its own for restoring it. Short loops *are* weird.
Point taken :-)
Can we come up with a one-sided parsing rule for syntactically valid cases?
That is, a rule that says guarantees that some constructs are syntactically
valid, but doesn't necessarily say anything about other constructs.
(I'm thinking of something like the last paragraph of users/23696, though
I have no opinion on what the rule should be. My only intersection with
shortloops is that I use the short form of 'for' in interactive shells.)
Cheers,
Daniel
next prev parent reply other threads:[~2018-10-05 13:27 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20181004154947epcas4p2441e109a2c4e060bf39f0f6925e98241@epcas4p2.samsung.com>
2018-10-04 15:49 ` Bart Schaefer
2018-10-04 16:31 ` Peter Stephenson
2018-10-04 20:04 ` Marc Chantreux
2018-10-04 20:37 ` Bart Schaefer
2018-10-05 6:04 ` Marc Chantreux
2018-10-04 20:34 ` Bart Schaefer
2018-10-05 9:14 ` Peter Stephenson
2018-10-05 13:26 ` Daniel Shahaf [this message]
2018-10-05 13:47 ` Peter Stephenson
2018-10-05 17:04 ` Daniel Shahaf
2018-10-06 1:47 ` Bart Schaefer
2018-10-06 11:15 ` Peter Stephenson
2018-10-06 11:55 ` Peter Stephenson
2018-10-06 18:21 ` Peter Stephenson
2018-10-07 3:51 ` Bart Schaefer
2018-10-07 18:16 ` Bart Schaefer
2018-10-08 10:07 ` Peter Stephenson
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