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Groups > gnu.bash.bug > #14895

[minor] for/select parsing inconsistency

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From Martijn Dekker <martijn@inlv.org>
Newsgroups gnu.bash.bug
Subject [minor] for/select parsing inconsistency
Date Fri, 7 Dec 2018 14:02:49 +0100
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There is a minor inconsistency in grammatical parsing between 'for' and 
'select' loops. Since 'select' is basically a glorified 'for', it seems 
to me that they should parse the same way.

$ bash -c 'for x in; do :; done'
$ bash -c 'select x in; do :; done'
bash: -c: line 0: syntax error near unexpected token `;'
bash: -c: line 0: `select x in; do :; done'
$ bash -c 'foo=; select x in $foo; do :; done'
$

An empty iteration argument list is not accepted by 'select', unless it 
results from an expansion. 'for' does accept this.

On ksh93, mksh, and zsh, both 'for' and 'select' accept a literal empty 
list. On shells without 'select' (dash, yash), 'for' accepts it.

So it seems to me that 'select' on bash should change to match 'for'.

Thanks,

- M.

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[minor] for/select parsing inconsistency Martijn Dekker <martijn@inlv.org> - 2018-12-07 14:02 +0100

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