The problem is that A::B is both a package name and a sub name. The difference is whether or not Perl knows A::B is a sub when A::B->new() is compiled.

When barewords are involved like in

A::B->new()

Perl must guess at what it means. Perl usually guesses the above means

"A::B"->new()

but if A::B is known to be a function, Perl will take that as a hint that you meant

A::B()->new()

where A::B is presumably a function that returns a class name or an object.

So why does test1.pl know A::B is a function name while test2.pl doesn't? The order in which they compile sub A::B relative to A::B->new varies.

test1.pl

1. Compile use A; 2. Execute require A; 3. ... 4. Compile sub B { ... } 5. ... 6. Execute A->import(); 7. Compile my $test = A::B->new(test => 1); as A::B()->new 8. Execute my $test = A::B->new(test => 1);

test2.pl

1. Compile require A; 2. Compile my $test = A::B->new(test => 1); as "A::B"->new 3. Execute require A; 4. ... 5. Compile sub B { ... } 6. ... 7. Execute my $test = A::B->new(test => 1);

Also see recent thread Bug or inconsitency? FQN of Package and sub name identical.

PS - Please use <c>...</c> around your code instead of <pre>...</pre>. It handles escaping, auto-wrapping, and makes the code easier to download.


In reply to Re: use vs. require by ikegami
in thread use vs. require by reneeb

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