Calling $function from $module

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

Replies are listed 'Best First'.
Re: Calling $function from $module by ikegami (Patriarch) on Aug 05, 2015 at 22:41 UTC
The equivalent of `$invocant->$method_name( @args )` [download] is `($module.'::'.$function_name)->( @args ) # Perl 5.6+` [download] or `&{ $module.'::'.$function_name }( @args )` [download] `use strict qw( refs );` forbids these (as it should), so you can use the following: `my $ref = do { no strict qw( refs ); \&{ $module.'::'.$function_name } }; $ref->( @args )` [download] Except it turns out that `\&{...}` is exempt from strict reference enforcement, so you can simply use `my $ref = \&{ $module.'::'.$function_name }; $ref->( @args )` [download] or even `( \&{ $module.'::'.$function_name } )->( @args )` [download] This trick to bypass strict reference enforcement is ~~not~~ documented.	[reply] [d/l] [select]
Re^2: Calling $function from $module by stevieb (Canon) on Aug 05, 2015 at 23:11 UTC
"These tricks to by pass strict reference enforcement are not documented." Nor should they be, imho.	[reply]
Re^3: Calling $function from $module by Anonymous Monk on Aug 05, 2015 at 23:13 UTC
These aren't tricks and they are documented Also Symbol::qualify_to_ref	[reply]
Re^4: Calling $function from $module by stevieb (Canon) on Aug 05, 2015 at 23:32 UTC
Re^4: Calling $function from $module by ikegami (Patriarch) on Aug 07, 2015 at 20:34 UTC
Re^2: Calling $function from $module by Anonymous Monk on Aug 06, 2015 at 00:13 UTC
Thank you so much -- this is great!	[reply]
Re: Calling $function from $module by BrowserUk (Patriarch) on Aug 05, 2015 at 22:19 UTC
Does this help? `package fred; sub fred{ print "This is fred::fred; so good they named me twice!" };; package main; fred::fred;; This is fred::fred; so good they named me twice! $p= 'fred'; $s='fred';; &{ "$p\:\:$s" };; This is fred::fred; so good they named me twice! *{ "$p\:\:$s" }->();; This is fred::fred; so good they named me twice!` [download] Anyone got any experience of this phone's predecessor? With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". I knew I was on the right track :) In the absence of evidence, opinion is indistinguishable from prejudice. I'm with torvalds on this Agile (and TDD) debunked I told'em LLVM was the way to go. But did they listen!	[reply] [d/l]
Re^2: Calling $function from $module by Anonymous Monk on Aug 05, 2015 at 22:27 UTC
'fred::fred'->();;	[reply]
Re^3: Calling $function from $module by BrowserUk (Patriarch) on Aug 05, 2015 at 22:40 UTC
And? If the OP could type `'fred::fred'->()` into his source code, then he could equally as easily type `fred::fred()` into his source code. Anyone got any experience of this phone's predecessor? With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". I knew I was on the right track :) In the absence of evidence, opinion is indistinguishable from prejudice. I'm with torvalds on this Agile (and TDD) debunked I told'em LLVM was the way to go. But did they listen!	[reply] [d/l] [select]
Re^4: Calling $function from $module by ikegami (Patriarch) on Aug 05, 2015 at 22:43 UTC
Re^5: Calling $function from $module by BrowserUk (Patriarch) on Aug 05, 2015 at 23:23 UTC
Re^4: Calling $function from $module by Anonymous Monk on Aug 05, 2015 at 22:57 UTC
Re: Calling $function from $module (can) by tye (Sage) on Aug 06, 2015 at 03:29 UTC
`$module->can($function)->( @args );` [download] - tye	[reply] [d/l]
Re: Calling $function from $module by stevieb (Canon) on Aug 05, 2015 at 22:32 UTC
Could you provide some context in which you need to use this type of syntax?	[reply]
Re^2: Calling $function from $module by Anonymous Monk on Aug 05, 2015 at 23:18 UTC
I'm refactoring a big if/else decision tree that sets some `$args`, loads a module, possibly does other random stuff, and then calls a function from that module. Previously each `elsif` had contained code to set `$args`, load the module, do the random stuff, and call the function. Being able to call `( &{ $module.'::'.$function } )->( $args );` gets rid of much of the repetitive code.	[reply] [d/l] [select]