Oh monks,

Here's the issue. I need to load a method conditionally, the condition being that a certain module Foo::Bar is usable. So after asking in the chatterbox, the following snippet arose: 

eval "use Foo::Bar";

unless ($@) {
    sub my_method { # Code }
}

[download]

So far so good. It worked for a trivial test subroutine, but not for my real-life example. The thing is, Foo::Bar = PDL. And PDL adds a lot of new syntax. Now, the eval expression is being executed at runtime, but the  my_method block has its syntax checked at compile time. So by the time that the syntax of the my_method is checked, PDL hasn't been loaded yet, and the module gives a syntax fatal error when the sub tries to

$matrix(0,0) = $value;

[download]
which is perfectly legal if PDL is loaded.
Also, I can't use  eval { use Foo::Bar }, because it dies on me if Foo::Bar isn't present.

I might be missing something here, but I surely don't know how to solve this. I would really appreciate some enlightenment!

In reply to Conditional loading of methods by bruno

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