ashmoran

module Chapter08
  module ReplaceTypeCodeWithStateOrStrategy
    class RigidMountainBike
      def initialize(params)
        @tyre_width = params[:tyre_width]
      end
      
      def off_road_ability
        @tyre_width * MountainBike::TYRE_WIDTH_FACTOR
      end

ashmoran

# Yet another version with suggestions from workmad3 :-)
# This time, pass in the keyword args into the block.
# This means duplicating the definition of valid params, but
# also means you get normal local variables in the method body.

module DefK
  # NOTE: params is for syntactic sugar, and has no bearing on the
  # number of arguments you can call
  def def_k(method_name, *params, kparams, &method_body)
    define_method method_name do |*args|

ashmoran

def make_me_an_animal_class(name, property)
  klass = Class.new

  klass.class_eval do
    define_method(:initialize) do |attribute|
      instance_variable_set("@#{property}", attribute)
    end
  
    define_method(property) do
      instance_variable_get("@#{property}")

ashmoran

class ArduinoInterpreter
  def initialize(setup_block, tick_block)
    @setup_block, @tick_block = setup_block, tick_block
  end
  
  def serial_begin
    puts "Initialising serial port..."
  end
  
  def serial_write(data)

ashmoran

<?php
::

ashmoran

(define (f n)
  (cond ((= n 1) 1)
        ((= n 2) 2)
        ((= n 3) 3)
        (else (+ (f (- n 1))
                  (* 2 (f (- n 2)))
                  (* 3 (f (- n 3))))))
  )

(define (g n)

ashmoran

(define (expect actual expectation expected)
  (display "• ")
  (display actual)
  (display " should equal ")
  (display expected)
  (display ": ")
  (expectation actual expected)
  (display "pass\n")
  )
  

ashmoran

; Slow!  The (next) "optimisation" slows it down 
(define (find-divisor n test-divisor)
  (define (next n)
    (if (= n 2)
      3
      (+ n 2)))
  (cond ((> (square test-divisor) n) n)
        ((divides? test-divisor n) test-divisor)
        (else (find-divisor n (next test-divisor)))))

ashmoran

(define (expect actual expectation expected)
  (display "• ")
  (display actual)
  (display " should equal ")
  (display expected)
  (display ": ")
  (expectation actual expected)
  (display "pass\n")
  )
  

ashmoran

(define (expect actual expectation expected)
  (display "• ")
  (display actual)
  (display " should equal ")
  (display expected)
  (display ": ")
  (expectation actual expected)
  (display "pass\n")
  )