Re: How called was &I?

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.";

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Re: Re: How called was &I? by rir (Vicar) on Sep 16, 2002 at 00:58 UTC
`method $obj $arg;` is not an error. `"Classname"->method( $arg); method "Classname" $arg; method( "Classname", $arg);` [download] The first two act just like the last one. Not so. Consider: `#!/usr/bin/perl -w use strict; package Base; sub base { print "Base::base called\n"; } package Derived; use vars qw( @ISA); @ISA = ( "Base"); package main; Derived::base Derived "hello"; Derived::base( Derived,"hello"); # undefined Derived::base "Derived" "hello"; # syntax error` [download]	[reply] [d/l] [select]
Re: Re: Re: How called was &I? by sauoq (Abbot) on Sep 16, 2002 at 02:22 UTC
`method $obj $arg;`is not an error. You are right. It isn't. I don't know what I was thinking. Before going on, I should clarify my point. Once a method is called, there is no way to determine the syntax used to invoke it. Your addition of a Derived class does nothing to show otherwise. That said, I made a couple of poor assumptions. One was that `"Classname"` in the original wasn't really meant to be a quoted string but a bareword. I also assumed that `method` would be the appropriate name for the method regardless of context. There really was no good reason to assume either and I should have requested clarification. `# Actual original post # What I assumed the OP meant "Classname"->method( $arg); # Class->method($arg); method "Classname" $arg; # method Class $arg; method( "Classname", $arg); # Class::method(Class, $arg);` [download] Mistakes, assumptions, and mistaken assumptions aside, if I understand the original post, the answer is still "No." -sauoq "My two cents aren't worth a dime.";	[reply] [d/l] [select]