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Do yourself a favour and implement a dispatch table. This additional level of indirection may seem a maintenance burden, but it will sure pay off in the long run. You will know exactly when and why it's failing, and you will also minimize the risk of malicious code injection.

Here's a sketch:

#!/usr/bin/perl use strict; use warnings; use Carp; { my %actions = ( one => \&one, two => \&two, three => \&three ); sub dispatch { # detect early all invalid arguments my @invalid = grep {!exists($actions{$_})} @_; if (@invalid) { local $" = ', '; croak("invalid action(s): (@invalid)"); # or the death spell of your choice } # else { for (@_) { # call $actions{$_}->(...), for example: $actions{$_}->("<<$_>>"); } # } } } # stub subs generator for exemplification only BEGIN { eval 'sub ' . $_ . q{ { local $" = ', '; print "sub [@{[(caller 0)[3]]}] with args: (@_)\n"; }} for qw/one two three/; } dispatch(qw/one two three/); dispatch(qw/three two one kaboom silence/);

Don't just cut and paste my code. I don't have the slightest idea about what you're trying to do with your program. The code above is not substitute for your own judgement.

P.S. If you decide to use symbol tables instead of plain hashes for lookup, as other people have suggested in this thread, try to use a separate namespace for this purpose and not main::. "Whitelisting" is important from a security perspective.


In reply to Re: Canon concerning coderef calls? by calin
in thread Canon concerning coderef calls? by jobi

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