Re^3: undef vs empty string '' from split

[Joost]

Hmm.. You mean like this:

#!perl -w
use strict;
$_ = 'event_handler=';
my ($var1, $var2) = split( /=/);
if( !defined($var2) ) {
    print "undefined\n";
}
else {
    print "'$var1' '$var2'\n";
}

output:

'event_handler' ''

that does seem to be inconsistent with the docs. And what's even more confusing is that:

#!perl -w
use strict;
$_ = 'event_handler=';
my @arr = split(/=/);
my ($var1, $var2) = @arr;
if( !defined($var2) ) {
    print "undefined\n";
}
else {
    print "'$var1' '$var2'\n";
}

output:

undefined

Confirms the docs.

updated: added output for perl 5.8.8 / linux

[Sidhekin]

split says:

When assigning to a list, if LIMIT is omitted, or zero, Perl supplies a LIMIT one larger than the number of variables in the list,

So while @arr = split gets a LIMIT of 0 (and stripping of trailing null fields), ($x, $y) = split gets a LIMIT of 3 (and no such stripping).

Another special case — potentially (as you, um, realized) surprising — but at least documented.