in reply to How do I import a global variable form a package with require?

A->import happens at runtime, but use happens at compile time. The strict check happens at compile time, too, so use a BEGIN block to run the import before the variable is encountered: 
BEGIN {
    require A;
    A->import(':all');
}
print $var;

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map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

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Re^2: How do I import a global variable form a package with require?
by haj (Vicar) on Jul 22, 2021 at 14:30 UTC
    Alternatively, declare the variable for the compiler. The call to import then assigns the value. This prints 7 (with your A.pm): 
    #! /usr/bin/env perl

use strict;
use warnings;

our $var;

use lib '.';
require A;
A->import (':all');

print $var . "\n";

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Re^2: How do I import a global variable form a package with require?
by nysus (Parson) on Jul 22, 2021 at 13:58 UTC

    Ah, yes, I remember that. However, what if I want to only import $var at runtime? Am I just stuck fully qualifiying it with A::var? And I still don't get why sub1 imports just fine with require and $var doesn't.

    $PM = "Perl Monk's";
    $MCF = "Most Clueless Friar Abbot Bishop Pontiff Deacon Curate Priest Vicar";
    $nysus = $PM . ' ' . $MCF;
    Click here if you love Perl Monks

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      > what if I want to only import $var at runtime?

      What does it mean? If you have code that will be compiled at runtime, it works: 

      require A;
A->import('$var');
eval 'print $var; 1' or warn $@;

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      > why sub1 imports just fine with require and $var doesn't

      Strict checks that variables are declared before you use them. It doesn't check subs when it's sure it's a sub, i.e. when parentheses follow the sub name. Try using sub1 without parentheses: the compiler will only see a bareword, not a sub call, and will complain.

      Update: reworded.

      map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
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        OK, that helps clear things up. Thanks for your help!

        $PM = "Perl Monk's";
        $MCF = "Most Clueless Friar Abbot Bishop Pontiff Deacon Curate Priest Vicar";
        $nysus = $PM . ' ' . $MCF;
        Click here if you love Perl Monks

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