Hello monks.

I suppose recursive 'uses' should be avoided in general cases, but still, I'd like to understand what's going on with this simple code: A1 and A2 are using C, which uses A2. Warning and strict are used in all files.

File A1.pm

package A1;
use A2;
use C;
sub functionA
{
    print "In A1: ".C::TYPE->{VEG}."\n";
    A2::functionA();
}

[download]

File A2.pm

package A2;
use C;
sub functionA
{
    print "In A2: ".C::TYPE->{VEG}."\n";
}

[download]

File C.pm

package C;
use A2;
use constant {
    TYPE => {
        FRUIT => 1,
        VEG => 2,
        MEAT => 3,
    },
};

[download]

Now we can test:

use A2;
A2::functionA(); # prints "In A2: 2"

[download]

and

use A1;
A1::functionA(); # prints "In A1: 2\nIn A2: 2"

[download]

Right. But if we inverse the order of 'use' in A1.pm, so C is 'used' before A2, the second test leads to a non-understanding of external constant TYPE: "Can't use bareword ("C::TYPE") as a HASH ref while "strict refs" in use at A2.pm line 7". Why so?

Question 2: If we keep this order, I can fix the problem by calling in A2.pm "C->TYPE->{VEG}" instead of "C::TYPE->{VEG}". Enlightenments welcome! : )

Cheers.

Locinus (perl v5.12.3 built for MSWin32-x86-multi-thread)

In reply to Behaviour on recursive use by locinus33

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