It occurs to me (after much interpolation) that you have seen the idiom use Some::Module qw/arg1 arg2/; i.e. passing compile time arguments to a module, and are asking about the implementation of it [the idiom].

Declaring the sub Some::Module::import facilitates this. The list of compile time args, if any, preceded by the module name, are passed to the sub by the compiler (thus Some::Module::import behaves as a class method) when the module is used.

This effect can be observed by considering the oft-quoted equivalence of the following 2 snippets:

use Foo qw/arg1 arg2/;
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and

BEGIN {
    require Foo;
    Foo->import(qw/arg1 arg2/);
}
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