when a user says: "use module 1.0.0", and I'm working in module "2.0.0"? My 2.0.0 module would never get called as far as I can tell...no?

What have you tried so far? What evidence do you have that supports your assumption?

The easy way to do that is to separate "module version" and "API version", and have the use line pass the API version as parameter. I recommend making the main module just a stub module and having "::API*" modules as submodules that get loaded resp. instantiated depending on what the user wants.

For example, a module could implement API1 and API2 in the following structure:

package My::Module;
use strict;
sub import {
    my ($class, %args) = @_;
    ...
    # Dynamically load either My::Module::API1 or My::Module::API2
};

[download]
package My::Module::API1;
# The old API

[download]
package My::Module::API2;
# The new API

[download]

User code would then use it in the following way:

use My::Module api => 'API1';
...

[download]

Look at require and/or use to see how to do dynamic module loading.

In reply to Re: How do you do multi-version modules? by Corion
in thread How do you do multi-version modules? by perl-diddler

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