Dear Monks:

This is once more a question to a problem which I have already solved in a different way, but where I would like to know why my first attempt failed.

Inspired by a suggestion I got for a different problem, I now wanted to solve the following task: Write a module Master.pm which, when called like this: 

package Slave;
use Master;

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would cause a function nx defined inside the package of Slave. My first attempt went like this: 
package Master;
use strict; use warnings;
sub import {
    my $target = caller;
    no strict 'refs';
    *{"$target\::nx"} = sub { do_something() }
}

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Using the debugger, I indeed could see that this function would end up in the symbol table of package Slave; but when I defined do_something as: 
package Slave;
use strict; use warnings;
use Master;
sub do_something { my $pkg=caller(); print "$pkg\n"; }

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I found that this prints Master, not Slave as the calling package. This puzzled me. Well, I ended up writing the defining line in the import function like this: 
eval "package $caller; sub nx { do_something() }";

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and this works now as expected, but I still would like to know why my original attempt had failed.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Defining a function in the caller's package by rovf

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