write ruby with python style whitespace (a haml hack)

hamrbl.rb

require 'rubygems'
require 'haml'
# Put a - char on each line in just the right place.
# (Need to remove blank lines too, they cause problems)
haml_source = File.read($0).gsub(/\n+/,"\n").gsub(/^\s*/,'\&-')
begin
  # Run the file with haml
  Haml::Engine.new(haml_source).render
rescue Exception => e
  # Spit out the haml source to make it easier to find your error
  puts "FAILED!\n#{haml_source}"
  raise e
end
exit
# Here's a one line version :)
# Haml::Engine.new(File.read($0).gsub(/\n+/,"\n").gsub(/^\s*/,'\&-')).render; exit

test.rb

#!/usr/bin/ruby -r hamrbl

# Just a test of hamlrb.rb

module Singing
  def sing(count=1)
    count.times do |i|
      if %w[tweety bigbird].include? @name.downcase
        puts "#{@name}: 'tweet tweet #{i+1}'"
      else
        puts "#{@name}: 'la la la #{i+1}'"

class Singer
  include Singing

  def initialize(name)
    @name = name

# comments are okay :)
Singer.new('Thom').sing(2)
Singer.new('Tweety').sing

zzoutput

$ ls -l
total 24
-rw-r--r--  1 simon  staff  232 17 Nov 21:13 hamrbl.rb
-rwxr-xr-x  1 simon  staff  433 17 Nov 21:56 test.rb
$ ./test.rb 
Thom: 'la la la 1'
Thom: 'la la la 2'
Tweety: 'tweet tweet 1'
$ 

See blog post at http://simonbaird.blogspot.com/2010/11/hamrbl-write-ruby-with-python-style.html