use Perl

• Re: (Score:1)

  by Aristotle (5147)

  Mmm, neat! I wanted to get one little bit of syntactic sugar in there, but that made it more complicated than I was hoping:

  use strict;
  use warnings;
  
  package Calc;
  
  use base 'Exporter';
  our @EXPORT = qw( income expense monthly );
  
  sub income {
      my ( $type, $amount ) = @_;
      __PACKAGE__->new( $type, $amount );
  }
  
  sub expense {
      my ( $type, $amount ) = @_;
      __PACKAGE__->new( $type, -$amount );
  }
  
  sub monthly {
      my $self = shift;
      $self->{
  • Re: (Score:2)

    by ziggy (25) on 2005.01.15 11:23 (#37515) Journal

    That's a really good idea. Here's a different approach:

    no strict 'refs';
    sub monthly ($$$) {
        my ($function, $type, $amount) = @_;
        &$function($type, $amount * 12);
    }
    
    sub quarterly ($$$) {
        my ($function, $type, $amount) = @_;
        &$function($type, $amount * 4);
    }
    
    sub biweekly ($$$) {
        my ($function, $type, $amount) = @_;
        &$function($type, $amount * 26);
    }
    
    sub weekly ($$$) {
        my ($function, $type, $amount) = @_;
        &$function($type, $amount * 52);
    }
    
    monthly   income  => "Yak Milking", 1000;
    quarterly expense => "Hosting", 250;
    biweekly  expense => "Health Plan", 150;
    weekly    expense => "Dog Walking" => 100;

    (OK, I admit it. I've been inhaling from the scheme pipe [schemers.org] lately. ;-)

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    Parent

    • Re: (Score:1)

      by Aristotle (5147)

      Yuck. I don't think the Schemers have much more appreciation for symrefs than the Perlistas. :-)

      The difference is I wanted to be able to easily throw more qualifiers into the mix:

      sub bi {
          my $self = shift;
          $self->{ amt } /= 2;
          return $self;
      }
      
      # and later:
      
      bi monthly expense Whatever => 100;

      It didn't start out OO. Initially I tried to just pass closures up the call chain. That didn't work too well though: I had to check wantarray everywhere to do the printin