Hi all- What's the best way to call a set of functions when you have their names (but not references to them). I really want to avoid writing "one big switch". Here's the simplest kind of example:

file.txt: 

  set 5
  add 2
  mul 2

interp.pl: 

!/usr/bin/perl

use strict;

sub set {
        my ($var, $param) = @_;
        $var = $param;
        return $var;
}
sub add {
        my ($var, $param) = @_;
        $var = ($var + $param);
        return $var;
}
sub mul {
        my ($var, $param) = @_;
        $var = ($var * $param);
        return $var;
}

my $register = 0;
while( <STDIN> )
{
        my ($command, $param) = split " ", $_;
        print $command, "->", $param, "\n";

        if( $command eq 'set' ) {
                $register = set( $register, $param );
        } elsif( $command eq 'add' ) {
                $register = add( $register, $param );
        } elsif( $command eq 'mul' ) {
                $register = mul( $register, $param );
        } else {
                die "Unknown operator: $command\n";
        }

        print "currently: $register\n";
        print "------\n";

}

[download]

I'm not *actually* trying to write an asm interpreter, but it serves as a good example of where I want to take a reasonably complicated action based on data that's outside of my control (so please don't say "eval( <perl> )" right away ;^). The functions that I'm calling, I'll want to put in a separate module (ie: ops.pm) to make maintenance easier, but that's something for the future. Please feel free to suggest creative ideas as well, as I'm kindof stuck.

Thanks!

--Robert

In reply to Dynamically calling different functions? by Anonymous Monk

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