Re: Get code ready for a loop (and a little RFC)

[Veltro]

Hello Lady Aleena

Maybe you want to use the sub that you eventually create to be used by several programs...

There is a technique that I sometimes use to be able to use common functionality that is needed by several programs. And I don't want to repeat myself over and over so I put those in libraries that are commonly accessible. E.g. I have a simple "CommonFunctions.pm" file containing functions like "trim", "trimleft", "trimright". I will share this example how to achieve this because I think it might be usefull to you. I have added use examples below under __END__.

MySVG.pm

package MySVG ;

use strict ;
use warnings ;
use Exporter ;
use vars qw( @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS ) ;

@ISA = qw( Exporter );
@EXPORT = ( ) ;
@EXPORT_OK = qw( gen_y family_y  ) ;
%EXPORT_TAGS = ( SVGFunc => [qw( &gen_y &family_y )] ) ;

sub gen_y {
  my $gen = shift;

  my $multiplier  = $gen - 1;
  my $gen_y = 36 + ( 76 * $multiplier);

  return $gen_y;
}

sub family_y {
  my ($gen, $two_parents, $one_parent) = @_;

  my $multiplier = $gen - 1;
  my $modifier   = $two_parents ? 0 : $one_parent ? 18 : 38;
  my $family_y = (-18 + (-76 * $multiplier)) + $modifier;

  return $family_y;
}
1;
__END__

use examples (which should always work in case MySVG is in the same lo
+cation as your program):
- use MySVG qw( :SVGFunc ) ;
- use MySVG qw( gen_y ) ;

Ways to make perl find the lib in case it is somewhere else:
- Add location of MySVG to PATH environment variable
- use the perl -Idirectory switch
- In case only your current project uses it and the pm file is in say 
+"lib\MySVG\" and you are working on a file in lib\somewhere-else\:
  use File::Basename qw( dirname ) ;
  use lib dirname( dirname __FILE__ ) . '/MySVG' ;