Computer Science Canada

Random Ruby Ridiculousness
Author:  wtd [ Sun Jan 24, 2010 2:47 am ]
Post subject:  Random Ruby Ridiculousness
Ruby:
class Any
        def initialize(enum)
                @enum = enum
        end

        def ==(other)
                @enum.any? { |x| x == other }
        end
end

class All
        def initialize(enum)
                @enum = enum
        end

        def ==(other)
                @enum.all? { |x| x == other }
        end
end

module Enumerable
        def any
                Any.new self
        end

        def all
                All.new self
        end
end

if [1, 2, 3].any == 3
        puts "Whee!"
end
Author:  wtd [ Sun Jan 24, 2010 2:53 am ]
Post subject:  RE:Random Ruby Ridiculousness
Ruby:
class Fixnum
        def even?
                self % 2 == 0
        end
end

class Any
        def initialize(enum)
                @enum = enum
        end

        def method_missing(symbol, *args)
                @enum.any? { |x| x.send(symbol, *args) }
        end
end

class All
        def initialize(enum)
                @enum = enum
        end

        def method_missing(symbol, *args)
                @enum.all? { |x| x.send(symbol, *args) }
        end
end

module Enumerable
        def any
                Any.new self
        end

        def all
                All.new self
        end
end

if [1, 2, 3].any.even?
        puts "Whee!"
else
        puts "Whoa!"
end

if [1, 2, 3].all.even?
        puts "Gah!"
else
        puts "Wah!"
end
Author:  Insectoid [ Sun Jan 24, 2010 10:44 am ]
Post subject:  RE:Random Ruby Ridiculousness
I dunno what modules do, but I gather that you've made classes initialized by methods in a module which return boolean values from an expression.

What I don't understand is what
code:

def method_missing(symbol, *args)
does, or why you don't pass parameters into All and Any's constructors.
Author:  Tony [ Sun Jan 24, 2010 11:01 pm ]
Post subject:  RE:Random Ruby Ridiculousness
Ruby:

class Foo
   def method_missing(symbol, *args)
      puts "Foo is missing method '#{symbol}', with arguments '#{args}'"
   end
end

code:

> Foo.new.bar "baz"
Foo is missing method 'bar', with arguments 'baz'
=> nil


Any and All constructors _do_ get parameters, in a way that "baz" is a parameter in an above example. That is, parenthesis are not strictly necessary.

Recall that + is a method on Fixnum class.
code:

> 1.+(2)
=> 3

But we don't need to explicitly specify .method or (argument)
Author:  wtd [ Sun Jan 24, 2010 11:37 pm ]
Post subject:  RE:Random Ruby Ridiculousness
Minor clean-up:

Ruby:
class Fixnum
        def even?
                self % 2 == 0
        end
end

EnumerableWrapper = Struct.new :enum

class Any < EnumerableWrapper
        def method_missing(symbol, *args)
                @enum.any? { |x| x.send(symbol, *args) }
        end
end

class All < EnumerableWrapper
        def method_missing(symbol, *args)
                @enum.all? { |x| x.send(symbol, *args) }
        end
end

module Enumerable
        def any
                Any.new self
        end

        def all
                All.new self
        end
end

if [1, 2, 3].any.even?
        puts "Whee!"
else
        puts "Whoa!"
end

if [1, 2, 3].all.even?
        puts "Gah!"
else
        puts "Wah!"
end

:


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