#!/usr/bin/perl --
use strict;
use warnings;
use Data::Dump qw/ dd /;
# Creates a shortcut for calling Data::Dumper, writing dd is enough to call module
Main( @ARGV );
# main function, takes every file (as an argument) that is passed to @ARGV, might be command line or files
#that are read in
exit( 0 );
#not really a clue, maybe main exits if no arguments are passed to it

#This defines the subrotine Main which is called in line 6 (in my editor at least)
sub Main {
    dd( -argv, \@ARGV );
#calls Data::Dumper via reference => possibly to print which files are being passed as arguments (control function) 
    for my $ar ( @ARGV ){
    	    #a for loop to treat each file that has been passed as argument to @ARGV with the sub Sky
    	    # each individual file assigned to $ar is in turn passed as a parameter to the subroutine
       Sky( $ar );
    }
    Sky(6);
#not really a clue => Does that mean that the sub stops after six runs 
}

#defining subroutine Sky
sub Sky {
    my( $ra ) = @_;
    # variable for the argument(s) passed to the sub, @_ accepts every argument passed to sub, i.e. the files passed to main
    dd( -ra, $ra );
    #print data strucutre of the files -parameter -ra
    dd( -args, \@_ );
    #print data strucutre of the arguments passed to the subroutine
}


__END__
$ perl sky
("-argv", [])
("-ra", 6)
("-args", [6])

# explains what sky does
$ perl sky a b c
#if I were to pass a, b, c
("-argv", ["a", "b", "c"])
#@ARGV would contain ["a", "b", "c"]

#Lists individual files as they are passed to both the sub Sky and sub Main
("-ra", "a")
("-args", ["a"])
("-ra", "b")
("-args", ["b"])
("-ra", "c")
("-args", ["c"])

#Still no clue about the number, sorrry
("-ra", 6)
("-args", [6])