Re: ${var+set}, ${var:+nonempty} broken in current git

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

On Wed, Sep 05, 2018 at 06:21:36PM +0200, Martijn Dekker wrote:
> 
> I don't think discarding the result is enough. The unused word should
> not be evaluated in the first place.

That's exactly what EXP_DISCARD is meant to do.  Parse it but
don't evaluate anything with side-effects.

> With this patch applied, the following breakage still occurs:
> $ src/dash -u -c 'unset foo bar; echo ${foo+${bar}}'
> src/dash: 1: bar: parameter not set
> (expected: empty line, no error)
> ...which seems to suggest that ${bar} is evaluated even though foo is unset.

OK so clearly we still have a bug in how EXP_DISCARD is handled.
Let me dig deeper.

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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