our is a lexically scoped alias for a global variable. Will create the global if it didn't exist already.

See the following code:
#!/usr/bin/perl

our $a = "foo";

print "$a\n";


package Our;

print "$Our::a  <--shouldn't print anything here\n";
print "$main::a <--should print 'a' from the main symbol table here\n"
+;
print "$a       <--should also print 'a' from the main symbol table he
+re\n\t\tdue to lexically scoped alias\n";

[download]
Results are:
foo
        <--shouldn't print anything here
foo     <--should print 'a' from the main symbol table here
foo     <--should also print 'a' from the main symbol table here
                due to lexically scoped alias

[download]
By default any global variables you create automatically populate the "main" symbol table, %main::. With a package declaration you could change which symbol table you are populating when you declare unqualified variables.

But our is a lexical decalaration. In the case above the declaration was file scoped. That's why I still got something back when I gave it an unqualified print statement print "$a\n" after the package declaration.

Don't forget just because it's a lexically scoped variable, it's still an alias for a global variable. Hence when I reassigned $a = "foo" with the our declaration, I blew away the old value.

Any comments are welcome.
Cheers,
Kristina

In reply to Re: Perl keywords for declaring variables: my, our and local??? by krusty
in thread Perl keywords for declaring variables: my, our and local??? by jira0004

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