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Why does my array appear to be out of scope?

Stormdev
New User

May 8, 2009, 2:21 PM

Post #1 of 4 (1366 views)

Why does my array appear to be out of scope?	Can't Post

I have a piece of code that simply stumps me... This works:

Code

sub htmlTimeZonePopdown { 
    my $default  = shift; 
    my $html = ""; 
 
    my @TimeZoneRegions = ( 
        "Eastern Time Zone", 
        "Central Time Zone", 
        "Mountain Time Zone", 
        "Pacific Time Zone", 
        "Alaska Time Zone", 
         "Hawaii Time Zone", 
    ); 
	 
    $default = 0  if ($default eq ""); 
     
    foreach my $offset (0..scalar(@TimeZoneRegions)-1) { 
     
        my $selected =   ($offset == $default) ? "selected" : ""; 
         
        $html .=  qq~ <option value="$offset" $selected>$TimeZoneRegions[$offset]</option>\n ~; 
    } 
     
    return $html; 
}

But when I move the array outside of the subroutine, it stops working. In fact the array does not appear to exist at all to the subroutine. This does not work:

Code

my @TimeZoneRegions = ( 
    "Eastern Time Zone", 
    "Central Time Zone", 
    "Mountain Time Zone", 
    "Pacific Time Zone", 
    "Alaska Time Zone", 
    "Hawaii Time Zone", 
); 
 
sub htmlTimeZonePopdown { 
    my $default  = shift; 
    my $html = ""; 
 
    $default = 0  if ($default eq ""); 
     
    foreach my $offset (0..scalar(@TimeZoneRegions)-1) { 
     
        my $selected =   ($offset == $default) ? "selected" : ""; 
         
        $html .=  qq~ <option value="$offset" $selected>$TimeZoneRegions[$offset]</option>\n ~; 
    } 
     
    return $html; 
}

This has really got me puzzled. I'm running with -w and use strict in case that matters. Any insights? I'm running a Perl v5.8.8.

Thanks in advance!

Code

FishMonger
Veteran

May 8, 2009, 2:57 PM

Post #2 of 4 (1363 views)

Re: [Stormdev] Why does my array appear to be out of scope? [In reply to]	Can't Post

I'm unable to duplicate your problem, but I see another issue. Do you see it?

Code

[root@fc4dev ~]# cat stormdev.pl 
#!/usr/bin/perl 
 
use strict; 
use warnings; 
 
my @TimeZoneRegions = ( 
    "Eastern Time Zone", 
    "Central Time Zone", 
    "Mountain Time Zone", 
    "Pacific Time Zone", 
    "Alaska Time Zone", 
    "Hawaii Time Zone", 
); 
 
my $HTML = htmlTimeZonePopdown(); 
 
print $HTML; 
 
sub htmlTimeZonePopdown { 
    my $default  = shift; 
    my $html = ""; 
 
    $default = 0  if ($default eq ""); 
 
    foreach my $offset (0..scalar(@TimeZoneRegions)-1) { 
 
        my $selected =   ($offset == $default) ? "selected" : ""; 
 
        $html .=  qq~ <option value="$offset" $selected>$TimeZoneRegions[$offset]</option>\n ~; 
    } 
 
    return $html; 
}

Quote

[root@fc4dev ~]# ./stormdev.pl
Use of uninitialized value in string eq at ./stormdev.pl line 23.
<option value="0" selected>Eastern Time Zone</option>
<option value="1" >Central Time Zone</option>
<option value="2" >Mountain Time Zone</option>
<option value="3" >Pacific Time Zone</option>
<option value="4" >Alaska Time Zone</option>
<option value="5" >Hawaii Time Zone</option>

[edit adjusted a little error on my part]

(This post was edited by FishMonger on May 8, 2009, 3:02 PM)

Stormdev
New User

May 8, 2009, 5:07 PM

Post #3 of 4 (1354 views)

Re: [FishMonger] Why does my array appear to be out of scope? [In reply to]	Can't Post

Funny thing, when I test it in isolation, it works fine either way, but when included with the other functions in my script, it doesn't. Literally, I can edit that larger file and simply move the array out of the sub, placing it immediately before the sub and it stops working....

I don't immediately see the other issue. I notice that you called the function without an argument and it generated the warning. Other than that, I would normally use "our" instead of "my" when declaring the array when placed outside of the sub. I also have an unneeded comma on the last array element, but I read that was perfectly accepted Perl practice.

Am I missing something?

Thanks for checking it out, by the way!

FishMonger
Veteran

May 8, 2009, 5:34 PM

Post #4 of 4 (1351 views)

Re: [Stormdev] Why does my array appear to be out of scope? [In reply to]	Can't Post

You want to declare vars with "our" only when you need to create global vars, which is not very often. 99.8% of the time you should use "my" to create lexical vars even when they're outside of subs.

You'll need to post your code so I can see why you're having this issue.

(This post was edited by FishMonger on May 8, 2009, 5:35 PM)

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