Re: bash 'let' can give error

[Marc Herbert]

> let intentionally returns status 1 if the value was 0; and status > 1 if
> there was an error.  Why?  So you can do loops such as:
> 
> countdown=10
> while let countdown--; do ... ; done
> 
>> Why does this happen? Is it 'by design'?
> 
> Yes.  The same as for 'expr' which is standardized by POSIX to have the
> same behavior.

This is a design mistake: it trades a few characters for a lot of confusion.