Re^2: OOP: ->Coderef for calling Private Methods

> I do not see any reason for the difference.

I agree there is no logical reason for extra behaviour...

> And the docs are clear and complete here as it seems to me.

Sorry, I disagree! Till now, I couldn't find any other perldoc describing this feature , and perlop is just a condensed quick reference. IMHO Perl has to many special cases to rely on just 3 words in a quickref.

I think it's quite unknown, taking into consideration that most hacker prefere the _underscore_private_method() convention instead.

Even Merlyn's Book on Perl-Objects and Refrences doesn't list this behaviour, (at least it's not indexed)

For me it looks like the documentation should be improved!

Cheers Rolf

UPDATE: And what really makes my brain stumble, what is the expected behaviour when i call $obj->$code_ref() and code_ref doesn't point to a method (of the blessed package).

Am I supposed to run experiments to find it out?

Please can anyone give me a link to any documentation!

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Re^3: OOP: ->Coderef for calling Private Methods (possibilites?) by tye (Sage) on Dec 13, 2008 at 19:42 UTC
What are the possibilities that you can't decide between without experiments? `$obj->$code_ref(...)` is the same as `$code_ref->( $obj, ... )` and that seems pretty clear from the documentation. That the method is specified from a code ref would only change the fact that there is no need to look anything up in @ISA. code_ref doesn't point to a method Perl 5 has no concept of "method" separate from "sub" so it isn't possible for a code ref to point to something that isn't just the same as a method. Clearly you can use this technique to dispatch to something that can't be used as a regular method of a class since otherwise there would be little point in using the word "private" in the description. - tye	[reply] [d/l] [select]
Re^4: OOP: ->Coderef for calling Private Methods (possibilites?) by LanX (Saint) on Dec 13, 2008 at 19:47 UTC
> $obj->$code_ref(...) is the same as $code_ref->( $obj, ... ) and that seems pretty clear from the documentation. References ?	[reply]
Re^5: OOP: ->Coderef for calling Private Methods (possibilites?) by ccn (Vicar) on Dec 13, 2008 at 19:57 UTC
This? perlobj#Method-Invocation An object is simply a reference that happens to know which class it belongs to. A class is simply a package that happens to provide methods to deal with object references. A method is simply a subroutine that expects an object reference (or a package name, for class methods) as the first argument. ... Whatever is on the left side of the arrow, whether a reference or a class name, is passed to the method subroutine as its first argument.	[reply]
Re^6: OOP: ->Coderef for calling Private Methods (possibilites?) by LanX (Saint) on Dec 13, 2008 at 20:16 UTC
Re^7: OOP: ->Coderef for calling Private Methods (possibilites?) by ccn (Vicar) on Dec 13, 2008 at 20:27 UTC
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Re^6: OOP: ->Coderef for calling Private Methods (possibilites?) by ikegami (Patriarch) on Dec 13, 2008 at 20:03 UTC
Re^5: OOP: ->Coderef for calling Private Methods (possibilites?) by ikegami (Patriarch) on Dec 13, 2008 at 20:01 UTC
The second half of the documentation reads the right side is a method name or a simple scalar variable containing either the method name or a subroutine reference, and the left side must be either an object (a blessed reference) or a class name (that is, a package name). See perlobj. I don't see how it could be clearer that a reference is allowed.	[reply]
Re^6: OOP: ->Coderef for calling Private Methods (possibilites?) by LanX (Saint) on Dec 13, 2008 at 20:30 UTC
Re^7: OOP: ->Coderef for calling Private Methods (possibilites?) by ikegami (Patriarch) on Dec 13, 2008 at 20:34 UTC
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Re^3: OOP: ->Coderef for calling Private Methods by ccn (Vicar) on Dec 13, 2008 at 19:48 UTC
Perl 5.6 does not have that feature (perlop 5.6). That explains why hackers use underscores and merlyn did not mention it in his book. Perl doesn't care about `$code_ref` having to be a reference to a method. It's enough to be just a sub ref. The sub gets an `$obj` as first argument, that's all. Update: broken link fixed	[reply] [d/l] [select]
Re^4: OOP: ->Coderef for calling Private Methods (5.6?) by tye (Sage) on Dec 13, 2008 at 20:19 UTC
Perl 5.6 does not have that feature Testing 5.005_03 shows that even it had the feature of `$obj->$code_ref( ... )`, despite the 5.6 documentation not mentioning it: `$ perl5.00503 -e '$cr= sub { warn "( @_ )\n" }; "main"->$cr( "bar" )' ( main bar )` [download] - tye	[reply] [d/l] [select]
Re^4: OOP: ->Coderef for calling Private Methods by LanX (Saint) on Dec 13, 2008 at 19:50 UTC
Thank you that's helpful! 8 ) Do you agree that it could be more documented? Cheers Rolf	[reply]