project involves adding a method reach to all objects.

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In Ruby, all classes are derived from class object. Since methods can be added to classes at any time, it is possible to re-open object and add methods, which then belong to every object.

This project involves adding a method reach to all objects. The reach method is like the standard each method, except that it applies to the leaves of container objects. The each method operates on each member of the container, but reach operates recursively, entering members which are also containers and iterating through their contents. For our purposes, an object is just a container if it has an each method. For instance,

irb (main):001:0> load("reach2.rb")

=> true

irb (main):002:0> [4, 9, "fred", 11].each { |x| print x, "\n"

4

9

fred 11

=> [4, 9, "fred", 11]

irb (main):003:0> [4, 9, "fred", 11].reach { |x| print x, "\n"

4

9

fred

11

=> [4, 9,

"fred", 11]

irb (main):004:0> [4, [ "ding", "bat"] "fred", [1, 2, 3]].ea

4

["ding", "bat"]

fred

[1, 2, 3]

=> [4, ["ding", "bat"], "fred", [1, 2, 3]]

irb (main):005:0> [4, [ "ding", "bat"], "fred", [1, 2, 3]].re

4

ding

bat

fred

1

2

3

|=> [4, ["ding", "bat"], "fred", [1, 2, 3]]

irb (main): 006:0> 17.each { |x| print x, "\n" } NoMethodError: undefined method `each' for 17: Fixnum from (irb):6

from /usr/bin/irb:11:in `'

irb (main): 007:0> 17. reach { |x| print x, "\n" }

17

=> 17

irb (main): 008:0> { "mike" => 17, "bill" => 3, "sally" => 25, ["mike", 17]

["bill", 3] ["sally", 25]

["alex", 9]

|=> { "mike"=>17, "bill"=>3, "sally"=>25, "alex"=>9}

irb (main): 009:0> { "mike" => 17, "bill" => 3, "sally" => 25, mike

17

bill

3

sally

25 alex 9

|=> { "mike"=>17, "bill"=>3, 'sally"=>25,

"alex"=>9}

 

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