Re^5: Function name in a variable, can't recall the concept (introspection with ->can )

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Re^6: Function name in a variable, can't recall the concept (introspection with ->can ) by AnomalousMonk (Archbishop) on Apr 16, 2019 at 22:22 UTC
What about a base class? Do such classes always have a declared `@ISA` that is empty? Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^7: Function name in a variable, can't recall the concept (introspection with ->can ) by LanX (Saint) on Apr 17, 2019 at 09:09 UTC
Actually I don't understand the discussion anymore, if the OP was willing to inspect a class the natural solution would be ->can. If he wasn't inspecting a class ->can would do the job, too. Are there pathological cases where an approach might break? Of course, this is Perl, with high flexibility to bend internals. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^8: Function name in a variable, can't recall the concept (introspection with ->can ) by ikegami (Patriarch) on Apr 19, 2019 at 09:03 UTC
No, that's not true. If they're trying to resolve a method, then `->can` is correct. If they're trying to resolve a sub, then `->can` can fail The OP is looking for a sub.	[reply] [d/l] [select]
Re^6: Function name in a variable, can't recall the concept (introspection with ->can ) by ikegami (Patriarch) on Apr 19, 2019 at 08:53 UTC
So it is as I said. You're suggesting that we use `my $sub = @{ get_array_by_name($pkg, 'ISA') } ? get_sub_by_name($pkg, $name) : $pkg->can($name);` [download] instead of `my $sub = get_sub_by_name($pkg, $name);` [download] That's ludicrous.	[reply] [d/l] [select]
Re^7: Function name in a variable, can't recall the concept (introspection with ->can ) by LanX (Saint) on Apr 19, 2019 at 12:41 UTC
> get_sub_by_name which get_sub_by_name? Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^8: Function name in a variable, can't recall the concept (introspection with ->can ) by Veltro (Hermit) on Apr 19, 2019 at 13:51 UTC
He probably means something hypothetical... I was actually thinking about this seriously, and I would likely do something as: `sub get_sub_by_name { my ($pkg, $name) = @_ ; no strict 'refs' ; if ( exists ${$pkg . '::'}{$name} ) { if ( ref ${$pkg . '::'}{$name} eq 'CODE' ) { return {$pkg . '::' . $name} ; } } ; }` [download] Maybe it can be written more pretty, and I don't know if any odd-cases are trapped (e.g. what about __ANON__) edit*: Comes to think of it, maybe the line 'exists' is not even needed?	[reply] [d/l]
Re^9: Function name in a variable, can't recall the concept (introspection with ->can ) by LanX (Saint) on Apr 19, 2019 at 15:23 UTC
Re^10: Function name in a variable, can't recall the concept (introspection with ->can ) by Veltro (Hermit) on Apr 19, 2019 at 17:30 UTC
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Re^8: Function name in a variable, can't recall the concept (introspection with ->can ) by ikegami (Patriarch) on Apr 19, 2019 at 18:03 UTC
Some code that gets a reference to the sub by name. What that code is doesn't matter, though it could be as simple as `\&{ $pkg . '::' . $name }`.	[reply] [d/l]
Re^9: Function name in a variable, can't recall the concept (introspection with ->can ) by LanX (Saint) on Apr 19, 2019 at 18:28 UTC
Re^10: Function name in a variable, can't recall the concept (introspection with ->can ) by ikegami (Patriarch) on Apr 19, 2019 at 18:41 UTC
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Re^7: Function name in a variable, can't recall the concept (introspection with ->can ) by LanX (Saint) on Apr 20, 2019 at 18:21 UTC
> You're suggesting that we use > `my $sub = @{ get_array_by_name($pkg, 'ISA') } ? get_sub_by_name($pkg, $name) : $pkg->can($name);` No, I don't! Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l]
Re^8: Function name in a variable, can't recall the concept (introspection with ->can ) by ikegami (Patriarch) on Apr 21, 2019 at 13:13 UTC
uh, then feel free to clarify why you meant by "one can easily check @ISA".	[reply]
Re^9: Function name in a variable, can't recall the concept (introspection with ->can ) by LanX (Saint) on Apr 21, 2019 at 14:00 UTC


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