How to pass command line arguments to perl script

We can pass command line arguments with the labels and we can make use of Getopt::Long module for achieving this

If an user tries to pass a wrong/invalid parameter, the following will throw an error.

The following script takes the parameters like
    -str (String value)
    -how_many_times (integer)
   
The following will print the string (from -str parameter) as many times the user the entered -how_many_times parameter

pass_command_line_params.pl

#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;
use Getopt::Long;
use File::Basename;

#Extract the nae of this script. 
my $scriptname = basename($0);

my @usage =("$scriptname",
           "-str  = Enter a String",
           "-how_many_times = Enter an integer, how many times you want the String to print");

my $opt_help     = 0;
my $opt_str     = ""; 
my $opt_how_many_times  = ""; 

my $ret = &GetOptions('help',  \$opt_help,
                      'str=s',\$opt_str,
                      'how_many_times=i',\$opt_how_many_times);


# Check parameters
if (($ret != 1) || (! $opt_str) || (! $opt_how_many_times)){
    &usage();
    exit;   
}

sub usage {
    print "\n How to use this Script : ". Dumper(\@usage) . "\n";

    print "\n You didn't pass str parameter " if (!$opt_str);
    print "\n You didn't pass how_many_times parameter " if (!$opt_how_many_times);
    print "\n";

    exit;
}


for (my $i=0; $i<$opt_how_many_times; $i++) {
    print $opt_str. "\n";
}
1;  

Outout :
1) perl pass_command_line_params.pl -str=Peter -how_many_times=

    Value "dd" invalid for option how_many_times (number expected)

    How to use this Script : $VAR1 = [
              'pass_command_line_params.pl',
              '-str  = Enter a String',
              '-how_many_times = Enter an integer, how many times you want the String to print'
            ];


    You didn't pass how_many_times parameter  

2) perl pass_command_line_params.pl -str="Mother Teresa" -how_many_times=5

    Mother Teresa
    Mother Teresa
    Mother Teresa
    Mother Teresa
    Mother Teresa  

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