Testing for empty string

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

What's the shortest/best way to test for an empty string ? I found a place where I foolishly used a simple if statement:

   if ($rc=$ref->getc) { .... }
[download]

Of course, that works fine until the string coming back happens to be 0x30 ... :(
"length(...)" seems like just a little bit too much work (for Perl).

   if ($rc=$ref->getc!~/./) { ... }
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won't work because the !~ binds tighter than the "=" (and perhaps it's a little too obscure). I'm just wondering if there is some simple idiom that I'm overlooking. Thanks !

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Re: Testing for empty string by chip (Curate) on Mar 19, 2004 at 02:58 UTC
I use `length()`: `if (length($rc=$ref->getc)) { ... }` But if that's the standard `getc()` then you probably want `defined()` instead. -- Chip Salzenberg, Free-Floating Agent of Chaos	[reply] [d/l] [select]
Re: Testing for empty string by graff (Chancellor) on Mar 19, 2004 at 03:11 UTC
`if ($rc=$ref->getc!~/./) { ... }` [download] won't work because the !~ binds tighter than the "="... So? That's what parens are for: `if (( $rc = $ref->getc ) !~ /./ ) { ... }` [download] I like parens -- they're Good Things. But the first reply was right: since you're using getc, you should just test for the return value being defined: `if ( defined( $rc = $ref->getc )) { ... }` [download]	[reply] [d/l] [select]