On Jul 15, Connie Chan said:
>### Lib 1 ###
>use strict;
>our %abc;
>$abc{a} = 1;
>$abc{b} = 2;
>### EOF Lib 1 ###
>
>### Lib 2 ###
>use strict;
>our $a = "ME";
>### EOF Lib 2 ###
You've made the mistake of using $a (or $b) as a variable name. These two
variables are protected from use strict 'vars', because they are used in
sorting routines:
my @sorted = sort { $a <=> $b } @numbers;
>### Script 1 ###
>use strict;
>eval { require "lib1.pl" } or die "lib 1";
>eval { require "lib2.pl" } or die "lib 2";
>
>print $abc{a};
>### EOF Script 1 ###
>
>When I run script 1, Perl throws me the err of 'explicit package',
>but if I change to print $a, instead of $abc{a}, I got "ME" correctly...
>Why ?
The our() declaration ONLY HAS EFFECT in the scope it is declared in.
That means it won't affect another file. And even MORE importantly,
require() happens AT RUN-TIME, and use strict 'vars' is a COMPILE-TIME
check. That means that even if you had put
use vars '%abc';
in the libraries, you wouldn't have been ok, because the libraries you
wrote get require()d. You could get around that with a BEGIN block, which
forces compile-time execution.
# foo.pl
use strict;
use vars '$x';
$x = 10;
# main.pl
use strict;
BEGIN { require "foo.pl" }
print $x; # no error :)
>Besides, how can I make some hash just like %ENV, so can access
>everywhere ?
You can create a variable (scalar, array, hash, even function!) that is
available in ALL packages by using a special caret-syntax:
package foo;
use strict;
${^name} = 1; # no error!
package bar;
use strict;
print ${^name}; # 1, no error!
--
Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/
RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/
** Look for "Regular Expressions in Perl" published by Manning, in 2002 **
<stu> what does y/// stand for? <tenderpuss> why, yansliterate of course.
[ I'm looking for programming work. If you like my work, let me know. ]
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