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From: rbj@uunet.UU.NET (Root Boy Jim)
Newsgroups: comp.lang.perl
Subject: Re: Checking if a variable is null
Keywords: perl null
Message-ID: <129570@uunet.UU.NET>
Date: 19 Apr 91 22:51:41 GMT
References: <483@cti1.UUCP>
Organization: UUNET Communications Services, Falls Church, VA
Lines: 25

In article <483@cti1.UUCP> kmeek@cti1.UUCP (Kevin Meek) writes:
?Is there a perl equivalent to the shell test operators -z and -n 

Yes, and it's builtin! The null string is false, and anything else
(except the string "0" when coerced to a number) is true.

?I want to print a line if certain parts are not null.
?
?What I'm using is this:
?
?($a,$b,$c) = split(' ');
?if ( $a ne '' && $b ne '' ) {
?   print $_;
?}

You can say: if ("$a$b") { print; }
Note that the default arg to print is $_.

?Is there a better way to check if a variable is null?
?i.e. print if -n $a 

How about "$a" && print "$a";
-- 
		[rbj@uunet 1] stty sane
		unknown mode: sane