Function call

akagrawal3 has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Function call by tobyink (Canon) on Mar 02, 2012 at 08:36 UTC
`%handler_for` is a hash, `$action` is a scalar. The value of `$handler_for{$action}` is either a coderef (a pointer to a sub) or if this is no-strict-refs code perhaps the name of a function as a string. `&{ $handler_for{ $action } }(%opts)` calls that function, passing it `%opts` as an argument. An alternative, perhaps clearer way of writing it might be: `my $function = $handler_for{$action}; $function->(%opts);` [download]	[reply] [d/l] [select]
Re: Function call by moritz (Cardinal) on Mar 02, 2012 at 08:53 UTC
Perl 5 does not support multi functions. What your piece of code does is calling an anonymous subroutine. See Higher Order Perl for more information. Another way to write this is `$handler_for{ $action }->(%opts)`. See perlreftut and perlref for more information. Perl 6 - second systems done right	[reply] [d/l]
Re^2: Function call by rovf (Priest) on Mar 02, 2012 at 09:01 UTC
Perl 5 does not support multi functions. Just being curious: What exactly is a multi function? I googled only this reference, where it says that multifunction is just another name for a multi-valued function. Since Perl can return lists (or sets), this would at least make it possible to model a multi-valued function easily. Is there maybe another meaning for the word "multifunction"? -- Ronald Fischer <ynnor@mm.st>	[reply] [d/l]
Re^3: Function call by eyepopslikeamosquito (Archbishop) on Mar 02, 2012 at 09:35 UTC
Perhaps moritz was referring to multimethods, aka multiple dispatch, which are provided by Perl 6 but not Perl 5.	[reply]
Re^4: Function call by moritz (Cardinal) on Mar 02, 2012 at 10:08 UTC
Re^4: Function call by tobyink (Canon) on Mar 02, 2012 at 10:07 UTC
Re^4: Function call by JavaFan (Canon) on Mar 02, 2012 at 10:05 UTC
Re^3: Function call by akagrawal3 (Beadle) on Mar 02, 2012 at 09:06 UTC
I actually meant that if it calls more than one function. I do not know the technical term for that.	[reply]
Re^4: Function call by ikegami (Patriarch) on Mar 02, 2012 at 09:15 UTC
Re^4: Function call by ikegami (Patriarch) on Mar 02, 2012 at 09:15 UTC
Re^2: Function call by akagrawal3 (Beadle) on Mar 02, 2012 at 09:11 UTC
Does that mean that if `%opts` has keys whose value is a subroutine name then in that case will it call all the subroutine(values of keys) of every key?	[reply] [d/l]
Re^3: Function call by moritz (Cardinal) on Mar 02, 2012 at 10:01 UTC
No. It's `handler_for{ $action }` that is the subroutine, and `%opts` is simply passed as the argument list to it. Perl 6 - second systems done right	[reply] [d/l] [select]
Re^4: Function call by akagrawal3 (Beadle) on Mar 02, 2012 at 10:49 UTC