Hello, fellow monks;
I've gotten some strange results for some code I'm writing. I've made a short test case which I hope somebody can explain the results of to me.
use strict;
use warnings;
my @arr = ('one', 'apple', 'two', 'apple', 'three');
my $var;
my $matches = 0;
foreach my $el (@arr) {
(defined($var) ? $var .= 'y' : $var .= 'n') if $el eq 'apple';
$matches++ if $el eq 'apple';
}
print "$var\n";
print "$matches\n";
$var = 'x';
$matches = 0;
foreach my $el (@arr) {
(defined($var) ? $var .= 'y' : $var .= 'n') if $el eq 'apple';
$matches++ if $el eq 'apple';
}
print "$var\n";
print "$matches\n";
Output:
nyn
2
xynyn
2
Nevermind rewriting the code bringing the assignment/appending operator outside of the comparison. I would like to know why this specific code prints such strange results (I would expect 'ny' for the former and 'xyy' for the latter fragment).
I understand '=' and '.=' can return something, but I don't understand how it gets assigned back to $var or why the non-matching part of the conditional gets executed.
What am I missing here?
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