SPUG: Question: scoping

Christopher Howard choward at indicium.us
Mon Sep 15 14:11:02 PDT 2008


Yello.  I was trying to figure out a certain concept, so I was creating 
a tiny test program.  Then I ran into something that didn't make sense 
to me.  Here's the code:

#!/usr/bin/env perl
use strict;
use warnings;
use MyClass;

my @obj;

for(my $i = 0; $i<10; $i++) {
    $obj[$i] = new MyClass;
}

for(my $i = 0; $i<10; $i++) {
    $obj[$i]->value("Test Value.");
}

1;


When I run this, I get "Can't call method "value" without a package or 
object reference at ./main.pl line 13." from the interpreter.  I was a 
bit confused, so I put constructor and de-constructor registration code 
into MyClass, to track was was happening to the objects.

 From what I can tell, the objects are getting destroyed before they 
leave the scope of the first for loop.  This leaves me still confused, 
because I declared @obj outside of the scopes of the for loops.

Is there some nuance of Perl syntax that I'm not understanding here?  
Any insight would be appreciated.

Obviously I could solve the immediate problem by putting them both in 
the same for loop.  But what I really want is to understand why the 
objects are going out of scope before I think they should be.



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