Well, method $obj $arg; would be an error. Update: Actually, that's not an error at all. rir++ for the catch. I updated the next paragraph to reflect this.

You can't distinguish between 

method( $obj, $arg);
$obj->method( $arg);
method $obj $arg;

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because they are simply all instance methods. The last two listed there act just like the first one.

Similarly, you can't distinguish between 

"Classname"->method( $arg);
method "Classname" $arg;
method( "Classname", $arg);

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because they are all class methods. The first two act just like the last one. Update: Poor assumptions made there. See rir's reply and mine to him for more insight. Otherwise, replace those examples with: 
Class->method($arg);
method Class $arg;
Class::method("Class", $arg);

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You can determine if the method was called as a class method or an instance method by checking the refness of the first argument but you can't determine the exact syntax.

Update: Sorry for the mess. As I understand the question, you want to know if, for example, a method can know whether it was invoked via indirect object notation, a normal sub call, or with the arrow operator. My answer: a very long "no." 
-sauoq
"My two cents aren't worth a dime.";

In reply to Re: How called was &I? by sauoq
in thread How called was &I? by rir

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