Hi there, I want to "decorate" perls built-in wantarray-function, but I can't find a way to do that. I want to do something like this: 
my $class = 'MyClass';
*CORE::GLOBAL::wantarray = sub {
    return CORE::wantarray(@_) if(!${"$class\::PRETEND_CONTEXT"});
    return 1 if(${"$class\::PRETEND_CONTEXT"} == 3);
    return 0 if(${"$class\::PRETEND_CONTEXT"} == 2);
    return undef if(${"$class\::PRETEND_CONTEXT"} == 1);
};

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But, not as for the build-in function caller(), this doesn't work and it throws the following error: 
Bareword found where operator expected at /usr/lib/perl/5.8/Data/Dumpe
+r.pm line 267, near "$realtype = $realpack ? Scalar::Util::reftype"
  (Might be a runaway multi-line ?? string starting on line 237)
        (Missing operator before Scalar::Util::reftype?)

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It seems to be, that wantarray isn't in CORE. But where it is? If I only redefine the function (in CORE::GLOBAL::) without calling the original function, all is ok. But I don't want that. How can I decorate it? Any suggestions? Tobiwan PS: if you want to try the code-snippet, you have to put it into the "import()" function of a class and you have to "use TheClass;". There is a write protection for the CORE:: Classes.

In reply to Overwrite built-in wantarray() by Tobiwan

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