in reply to How to call subroutines using variables ?

You probably shouldn't do that. It amounts to using symbolic references, which is disallowed by using strict.

It's probably better to use a reference to the subroutine instead of its name: 

#!/usr/local/bin/perl
use strict;
use warnings;

my $s = \&res;

$s->();

sub res {
 print "hai";
}

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edit: see also perlref

"What should it profit a man, if he should win a flame war, yet lose his cool?"

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Re^2: How to call subroutines using variables ?
by Trizor (Pilgrim) on Mar 22, 2007 at 23:02 UTC
    However AM said that they had a hash of sub names, possibly from a external library. If you cannot convert the hash of subroutine names to a hash of code references  $s{key}=\&valsub; then use a bare BLOCK to turn strict off only when calling subs from that hash: 
    { # Get an enclosing lexical scope
  no strict 'refs'; # allow symbolic refrence shenanigains
  &$SubHash{key}(); # Call sub
} # Back to strict 'refs'

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    or write a sub for this purpose (This assumes $SubHash is a global) 
    CallFromHash {
  no strict 'refs'; # allow symbolic refrence shenanigains
  return &$SubHash{shift(@_)}(@_); #Call the sub in the first arg with
+ the rest of @_ as args and return
}

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    However a hash of sub names is probably a bad idea to start with, and you should reconsider your design to use hard refs (mentioned by Joost) or remove the hash all together if possible.
    Update: Forgot Amperstands
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Re^2: How to call subroutines using variables ?
by bradcathey (Prior) on Jun 09, 2007 at 17:31 UTC

    I tried:

    my @all_subs = (\&sub_1,\&sub_2);
$all_subs[1]->();

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    which worked fine. But in CGI::Application I'm using $self->, as in:

    $self->$all_subs[1]->();

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    but got a syntax error (doesn't like the 2nd arrow operator). How can I get around this? Thanks.

    Update: fixed some punctuation


    —Brad
    "The important work of moving the world forward does not wait to be done by perfect men." George Eliot
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      which worked fine. But in CGI::Application I'm using $self->, as in:

      $self->$all_subs[1]->();

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      Use:

      my $code=$all_subs[1];
$self->$code();

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      This will call $code as a method on $self, which AIUI is what you want. If you would like to do the same without an intermediate variable, then I wondered too and it turns out to be possible, albeit in a somewhat convoluted way.

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        Worked great, but I did have to get rid of the & in front of my subroutine names. So:

        my @all_subs = (\sub_1,\sub_2);

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        —Brad
        "The important work of moving the world forward does not wait to be done by perfect men." George Eliot
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