Re: Using Getopt::Long to call subroutines

Reading commandline options with Getopt::Long is a good thing generally, but seems like overkill for your situation. You could simplify things a bit by using a dispatch table instead.

use strict;
use warnings;

my %dispatch = (
  one => \&sub1,
  two => \&sub2,
  three => \&sub3,
);

my $arg = shift @ARGV;
if (defined $arg && exists $dispatch{$arg}) {
    $dispatch{$arg}->();
} else {
  print "Usage: $0 [-command]\n";
  print "Available commands:\n";
  print " -$_\n" for sort keys %dispatch;
}

sub sub1 {
print "sub one";
}

sub sub2{
print "sub two";
}

sub sub3 {
print "sub three";
}
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Comment on Re: Using Getopt::Long to call subroutines Download Code

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Re^2: Using Getopt::Long to call subroutines by chinamox (Scribe) on Oct 22, 2006 at 04:10 UTC
thank you for your swift response! I think a dispatch table would be very useful for this simple example but in my actual program I am using @ARGV and the empty <> operator to pass data in from exterior files. want my command line too look something like this: `myusername $: perl myprogram.pl -two /mydire/programs/data` [download] This way I can run selected subroutines on selected files. Thanks for your help! -mox	[reply] [d/l]
Re^3: Using Getopt::Long to call subroutines by imp (Priest) on Oct 22, 2006 at 04:19 UTC
You can still use that method if you like, as by shifting $arg from @ARGV you remove it from the list of files that will be processed by `<>`. And you could still use the -two syntax if you liked, here's an example: `use strict; use warnings; my %dispatch = ( one => \&sub1, two => \&sub2, three => \&sub3, ); sub usage { print "Usage: $0 [-command]\n"; print "Available commands:\n"; print " -$_\n" for sort keys %dispatch; exit 1; } my $arg = shift @ARGV; usage() unless defined $arg; usage() unless $arg =~ /^-/; $arg =~ s/^-//; usage() unless exists $dispatch{$arg}; $dispatch{$arg}->(); sub sub1 { print "one: $_" for <>; } sub sub2{ print "two: $_" for <>; } sub sub3 { print "three: $_" for <>; }` [download]	[reply] [d/l] [select]