Localize the package global first, and then call the lvalue sub.

Thanks for your time but I've confused the issue a little by using a variable accessible from the current scope. I was specifically interested in why the particular corner I've backed myself into doesn't work. 
{
    my $foo = 1;
    sub level : lvalue {$foo}
}

print level();
{
    local level() = 2;
    print level();
}
print level();
__END__
122

[download]

I read local Foo->level = 2 as trying to localize an expression (the lvalue sub itself?), and not the package global this sub operates on.

Ah that's interesting, after reading your reply I've run B::Deparse on my new example (sans our'd package variables) and the local() is removed altogether: 
{
    my $foo = 1;
    sub level : lvalue {
        $foo;
    }
    ;
}
print level();
{
    level() = 2;
    print level();
}
print level();

[download]


Hmm? $Foo::level is no reference - calling Scalar::Util::refaddr on it yields undef.


I did \ my lvalues first :)

My testing methods may be unorthodox but it seemed like a simple way to asses if the local() had happened like I expected and the localized Scalar::Util::refaddr \$Foo::level; now pointed at a different address.

Presumably because perl has to create a new SV slot on the scratchpad for the inner scope the SV in question will have a different address when localized assuming everything goes well (I think I've got the lingo right?).

Cheers,
Shane.

In reply to Re^2: Localize lvalue subroutine. by shanna
in thread Localize lvalue subroutine. by shanna

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