perl parse command line options - perl

Question

I am trying to get parameters from command line and parse it and if the parameters are right call certain functions based on it.I am new to perl, can some one let know how to achieve this
script.pl aviator #switch is valid and should call subroutine aviator()
script.pl aviator debug #valid switch and should call subroutine aviator_debug
script.pl admin debug or script.pl debug admin #valid switch and should call subroutine admin_debug()
script.pl admin #valid switch and should call subroutine admin()
script.pl dfsdsd ##invalid switch ,wrong option

Answer 1

Since you are dealing with plain words (and not --switches), just look at #ARGV, which is an array of the command line options. Applying a simple if/elsif/etc to that data should serve your needs.
(For more complex requirements, I'd suggest the Getopt::Long::Descriptive module.)

Answer 2

Having lots of checks against specific strings is a recipe for a maintenance nightmare as your system grows more and more complex. I strongly recommend implementing some kind of dispatch table.
#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
my %commands = (
aviator => \&aviator,
aviator_debug => \&aviator_debug,
admin => \&admin,
admin_debug => \&admin_debug,
debug_admin => \&admin_debug,
);
my $command = join '_', #ARGV;
if (exists $commands{$command}) {
$commands{$command}->();
} else {
die "Illegal options: #ARGV\n";
}
sub aviator {
say 'aviator';
}
sub aviator_debug {
say 'aviator_debug';
}
sub admin {
say 'admin';
}
sub admin_debug {
say 'admin debug';
}

Answer 3

variant 1:
#!/usr/bin/perl
my $command=join(' ',#ARGV);
if ($command eq 'aviator') { &aviator; }
elsif ($command eq 'aviator debug' or $command eq 'debug aviator') { &aviator_debug; }
elsif ($command eq 'admin debug' or $command eq 'debug admin') { &admin_debug; }
elsif ($command eq 'admin') { &admin; }
else {print "invalid option ".$command."\n";exit;}
variant 2:
#!/usr/bin/perl
if (grep /^aviator$/, #ARGV ) {
if (grep /^debug$/, #ARGV) { &aviator_debug; }
else { &aviator; }
} elsif (grep /^admin$/, #ARGV ) {
if (grep /^debug$/, #ARGV) { &admin_debug; }
else { &admin; }
} else { print "invalid option ".join(' ',#ARGV)."\n";exit;}
exit;
variant 3:
#!/usr/bin/perl
use Switch;
switch (join ' ',#ARGV) {
case 'admin' { &admin();}
case 'admin debug' { &admin_debug; }
case 'debug admin' { &admin_debug; }
case 'aviator' { &aviator; }
case 'aviator debug' { &aviator_debug; }
case 'debug aviator' { &aviator_debug; }
case /.*/ { print "invalid option ".join(' ',#ARGV)."\n";exit; }
}

Answer 4

Here is my take on the problem
#!/usr/bin/perl
use 5.14.0;
my $arg1 = shift;
my $arg2 = shift;
given ($arg1) {
when ($arg1 eq 'aviator') {say "aviator"}
when ($arg1 eq 'admin' && !$arg2) {say "admin"}
when ($arg1 =~ /^admin|debug$/ && $arg2 =~ /^admin|debug$/) {say "admin debug"}
default {say "error";}
}