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Re: [ -n ] != [ -n "" ] in 2.05a
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From: |
Chet Ramey |
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Subject: |
Re: [ -n ] != [ -n "" ] in 2.05a |
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Date: |
Thu, 13 Dec 2001 10:27:41 -0500 |
> [ -n ] && echo "bug"
>
> will print "bug".
As it should.
> I'd have expected [ -n ] would be the same as [ -n "" ]...
Bad expectation.
> (Affects the variants thereof, as well, e.g.
> unset FOO
> [ -n $FOO ] && echo "bug")
Bad programming practice.
Look at question E1 in the Bash FAQ for an explanation. Equivalent
text appears in the bash man page.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
( ``Discere est Dolere'' -- chet)
Chet Ramey, CWRU chet@po.CWRU.Edu http://cnswww.cns.cwru.edu/~chet/