Re: how to declare a local *subname=sub{}?

I am very unsure as to your question and the intent of your code? I don't see the need for type glob (*something). What is your objective?

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

# dispatch table...
#
my %table = ('x'=>\&ABC,
             'y'=> sub {print "Anon sub for key 'y' in table\n";}
            );
            

sub ABC{print "sub ABC called\n";};  

# call routines in the dispatch table...

$table{'x'}->(); # prints: "sub ABC called"
$table{'y'}->(); # prints: "Anon sub for key 'y' in table"


# local can only "mask" an "our" or a global variable, like
# perhaps as in the common idiom:
#   my $file = do { local $/; <FILE> };
# which "slurps" an entire file into the $file variable.<br>
# A "my" variable cannot be "localized"

our $xyzzy = 33;
{
   local $xyzzy = 55;
   print "$xyzzy\n";   #prints 55
}
print "$xyzzy\n";      #prints 33
[download]

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Re^2: how to declare a local *subname=sub{}? by AnomalousMonk (Archbishop) on Oct 31, 2016 at 05:24 UTC
I am very unsure as to your question and the intent of your code? I share your uncertainty. I think perl-diddler may have invented yet another way to write spaghetti code without using goto. A dispatch table approach such as you exemplify tends to be my knee-jerk approach to the sort of problem that I imagiine gave rise to the OP. `# local can only "mask" an "our" or a global variable ... ... # A "my" variable cannot be "localized"` [download] I tend to think of this a bit differently. My conception is that a my variable can be completely "localized" or isolated within a scope, whereas an our (or package global) variable cannot. The potential scoped isolation of lexical variables makes it very easy to reason about them, a great advantage. c:\@Work\Perl>perl -wMstrict -le "our $xyzzy = 33; print qq{A: $xyzzy}; { local $xyzzy = 55; print qq{B: $xyzzy}; zot(); print qq{C: $xyzzy}; } print qq{D: $xyzzy}; ;; sub zot { $xyzzy = 99; } " A: 33 B: 55 C: 99 D: 33 c:\@Work\Perl>perl -wMstrict -le "my $xyzzy = 33; print qq{A: $xyzzy}; { my $xyzzy = 55; print qq{B: $xyzzy}; zot(); print qq{C: $xyzzy}; zonk(); print qq{D: $xyzzy}; } print qq{E: $xyzzy}; ;; sub zot { $xyzzy = 99; } ;; sub zonk { my $xyzzy = 9999; } " A: 33 B: 55 C: 55 D: 55 E: 99 [download] Update: But then there's PadWalker... (sigh) Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^3: how to declare a local *subname=sub{}? by Marshall (Canon) on Oct 31, 2016 at 06:27 UTC
We aren't that far off. `#!usr/bin/perl use strict; use warnings; our $xyzzy = 33; print "A: $xyzzy\n"; { local $xyzzy = 55; print "B: $xyzzy\n"; zot(); # changes $xyzzy altough no return value # zot() can modify a global variable print "C: $xyzzy\n"; } # $xyzzy is now back at the A: value print "D: $xyzzy\n"; sub zot { $xyzzy = 99; #set global "our" var } __END__ A: 33 B: 55 C: 99 D: 33` [download]	[reply] [d/l]