After years of sloppiness I'm finally using 'strict'. I ran into some unexpected behaviour while adding 'use strict' to a working program.

The main part of the program is a foreach loop on a list. To save myself passing the value of the loop variable to a lot of subs, I want the loop variable to be global.

I thought that 'my $loop_var' at the start of the program would make it's scope the entire file, but that's not happening. Example: 

use strict;

my @colors = qw ( red green blue );

my $color;  
my $light = 'on';

foreach $color (@colors) {
    print "\$color is '$color' and \$light is '$light' in loop, ";
    print_color();
}

####
sub print_color {
    print " in sub values are '$color' and '$light'\n";
}

[download]

gives: 

$color is 'red' and $light is 'on' in loop,  in sub values are '' and 
+'on'
$color is 'green' and $light is 'on' in loop,  in sub values are '' an
+d 'on'
$color is 'blue' and $light is 'on' in loop,  in sub values are '' and
+ 'on'

[download]

$light works as I expected, but $color doesn't make it to the subroutine. If I use 'our $color' instead of 'my $color', I get the expected results.

I'm trying to understand why the foreach loop appears to narrow the scope of $color when using 'my,' but not when using 'our.' Any explanations?

Thanks,

Queeg

In reply to strict, scope, my and foreach - not behaving as expected by queeg

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