Re: Surprise: scalar(($x, $y) = split)

Update: Everything below is wrong, as ambrus mentions in the reply. (Note to self: Self, just because you get the correct result doesn't mean that you got the right answer!)

ambrus:

You forgot some parenthesis:

(2==(my($x,$y) = split " ")) or die "wrong number of fieldsd";

Example:

$ cat foo.pl
use strict;
use warnings;
my $x; my $y;
while (<DATA>) {
    chomp;
    (2==0+(($x, $y) = split /:/,$_)) or print "wrong number of fields\
+n";
    print "<$_>, <$x>, <$y>\n";
}
__DATA__
FOO:BAR:BAZ:PLOVE
FOO:BAR:BAZ
FOO:BAR
BAZ
$ perl foo.pl
wrong number of fields
<FOO:BAR:BAZ:PLOVE>, <FOO>, <BAR>
wrong number of fields
<FOO:BAR:BAZ>, <FOO>, <BAR>
<FOO:BAR>, <FOO>, <BAR>
wrong number of fields
Use of uninitialized value $y in concatenation (.) or string at foo.pl
+ line 7, <DATA> line 4.
<BAZ>, <BAZ>, <>
[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

Comment on Re: Surprise: scalar(($x, $y) = split) Select or Download Code

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Re^2: Surprise: scalar(($x, $y) = split) by ambrus (Abbot) on Oct 28, 2011 at 14:05 UTC
It's not the parenthesis that helps there but <Reveal this spoiler or all in this thread>	[reply] [d/l]
Re^3: Surprise: scalar(($x, $y) = split) by roboticus (Chancellor) on Oct 28, 2011 at 14:21 UTC
ambrus: Ha, ha--color me surprised as well! Corrected example: $ cat foo.pl use strict; use warnings; my $x; my $y; while (<DATA>) { chomp; 2==(($x, $y) = split " ") or print "wrong number of fields\n"; print "<$_>, <$x>, <$y>\n"; } __DATA__ FOO BAR BAZ PLOVE FOO BAR BAZ FOO BAR BAZ $ perl foo.pl wrong number of fields <FOO BAR BAZ PLOVE>, <FOO>, <BAR> wrong number of fields <FOO BAR BAZ>, <FOO>, <BAR> <FOO BAR>, <FOO>, <BAR> wrong number of fields Use of uninitialized value $y in concatenation (.) or string at foo.pl + line 7, <DATA> line 4. <BAZ>, <BAZ>, <> [download] ...roboticus When your only tool is a hammer, all problems look like your thumb.	[reply] [d/l]