cc: shell-discuss at opensolaris.org don.cragun at sun.com pkchris at
users.sourceforge.ne
Subject: Re: Re: [ksh93-integration-discuss] CR 6791838 Created P3 shell/korn93
*ksh93* unset of a variablewhich is not set should return 0
--------
> Doesn't [[ ${x+y} ]] expand variable x?
> x= ; x.get() { print "hello" ; } [[ ${x+y} ]] ; print $?
> prints
> hello
> 0
> ${x+y} will be a big performance regression if compared to if (unset -e x)
>
> Chris
>
It currently does expand x, but I don't think that this is necessary
and I could change this. I could detect that x is followed by a + and just
check for not set.
However, ${x:+y} does need to expand x to see whether it is the empty string.
David Korn
dgk at research.att.com
