Conversion to boolean in Ruby

As you probably know, ruby doesn't have Boolean class, true and false are instances of their own classes TrueClass and FalseClass. Kernel module adds several methods for conversion between primitive types such as Array(), Integer(), Float() etc. to global space however Boolean() is lacking. Lets make it!

module Conversions

  module_function

  def Boolean(value)
    case value
    when true, 'true', 1, '1', 't' then true
    when false, 'false', nil, '', 0, '0', 'f' then false
    else
      raise ArgumentError, "invalid value for Boolean(): \"#{value.inspect}\""
    end
  end

end

Edit: As suggested by @dacoxall in commetns, Boolean() is now raising exceptions for not meaningful values.

Desired usage:

# 1. because of module_function, you can call it directly

puts Conversions.Boolean("true").class
# => TrueClass

# 2. or include module to your class or to the global space (as Kernel module does with Integer(), String(), etc.)

include Conversions
puts Boolean("true").class
# => TrueClass

Here is a gist with alternative implementations and benchmarks.

Do you have a better Boolean conversion implementation? Share it!