Hi Perlmonks,

I have a silly problem.

In a script I defined many constants through the constant module.
I want to implement a function that dumps all those constants when the script is invoked with a certain option.

To show you what I try to accomplish please have a look at the sample snippet below.

The only way I got access to the constants was through an eval(). But then it still fails if the constant holds a list of values.

I don't know if constants are at all part of the symbol table so my whole assumption of accessing them through symrefs may be absurd altogether.

Any suggestions?

#!/usr/bin/perl

use strict;

use constant { CLOUD => 9,
               HELL  => 'sytem administration' };
use constant   SINS  => qw(pride envy gluttony lust anger greed sloth)
+;

dump_consts();

sub dump_consts {

no strict 'refs';

print "SINS list:\t@{[SINS]}\n\n";

foreach my $const (keys %constant::declared) {
    printf "%-15s%6s => %s\n", 'eval:', $const, eval $const;
    printf "%-15s%6s => %s\n", 'symref:', $const, {$const};
    printf "%-15s%6s => %s\n", 'symref fqn:', $const, {"constant::$con
+st"};
    printf "%-15s%6s => %s\n", 'symref hash:', 
                                $const, join(' ', values %{$const});
}
}

[download]

This produces this output:

SINS list:      pride envy gluttony lust anger greed sloth

eval:          main::CLOUD => 9
symref:        main::CLOUD => HASH(0x4002da60)
symref fqn:    main::CLOUD => HASH(0x4002da60)
symref hash:   main::CLOUD => 
eval:          main::HELL => sytem administration
symref:        main::HELL => HASH(0x4005c5f0)
symref fqn:    main::HELL => HASH(0x4005c5f0)
symref hash:   main::HELL => 
eval:          main::SINS => pride
symref:        main::SINS => HASH(0x4005c5fc)
symref fqn:    main::SINS => HASH(0x4005c5fc)
symref hash:   main::SINS =>

[download]

In reply to Accessing constants via symbol table possible? by SIGSEGV

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