Re: sh emulation POSIX non-conformances (no word splitting upon arithmetic expansion)

[Vincent Lefevre <vincent@xxxxxxxxxx>]

On 2021-04-11 20:18:05 +0100, Stephane Chazelas wrote:
> 2021-04-11 18:57:26 +0100, Stephane Chazelas:
> > Some non-POSIX conformances I can think of ATM:
> [...]
> 
> Another one:
> 
> $ zsh --emulate sh -c 'IFS=2; printf "<%s>\n" $((11*11))'
> <121>
> 
> While POSIX (beleive it or not) requires:
> 
> <1>
> <1>
> 
> Again, that's one of the cases where many shells (most ash-based ones,
> pdksh, yash at least) behaved like zsh but switched for POSIX
> compliance (even though that hardly makes sense).

I disagree. I think that the fact that $((11*11)) behaves in
a way similar to parameter expansion makes more sense and is
less surprising:

$ sh -c 'foo=121; IFS=2; echo $foo $((11*11))'
1 1 1 1
$ zsh --emulate sh -c 'foo=121; IFS=2; echo $foo $((11*11))'
1 1 121
$ 

If something hardly makes sense, this is "IFS=2".

-- 
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <https://www.vinc17.net/>
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