Mercurial > repos > other > SevenLanguagesInSevenWeeks

annotate 1-Ruby/tree.rb @ 24:cd874e58dbc5

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Add code from book
author IBBoard <dev@ibboard.co.uk>
date Fri, 20 Jan 2017 20:59:01 +0000
parents e020410896ca
children
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1 #---
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2 # Excerpted from "Seven Languages in Seven Weeks",
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3 # published by The Pragmatic Bookshelf.
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4 # Copyrights apply to this code. It may not be used to create training material,
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5 # courses, books, articles, and the like. Contact us if you are in doubt.
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6 # We make no guarantees that this code is fit for any purpose.
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7 # Visit http://www.pragmaticprogrammer.com/titles/btlang for more book information.
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8 #---
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9 class Tree
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10 attr_accessor :children, :node_name
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12 def initialize(hash)
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13 if hash.size == 1
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14 @node_name = hash.keys[0]
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15 @children = hash[@node_name].collect { |key,value| Tree.new({ key => value }) }
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16 else
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17 @node_name = 'Root'
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18 @children = hash.collect { |key,value| Tree.new({ key => value }) }
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19 end
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20 end
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22 def visit_all(&block)
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23 visit &block
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24 children.each {|c| c.visit_all &block}
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25 end
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26
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27 def visit(&block)
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28 block.call self
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29 end
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30 end
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32 puts "Creating tree from hashes"
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33 hash_tree = Tree.new({'grandpa' => {'dad' => {'child1' => {}, 'child2' => {} }, 'uncle' => { 'child3' => {}, 'child4' => {} } } })
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34 hash_tree.visit_all {|node| puts node.node_name}
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35 puts "Testing non-tree hashes"
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36 hash_tree = Tree.new({'grandpa' => {'dad' => {'child1' => {}, 'child2' => {} }, 'uncle' => { 'child3' => {}, 'child4' => {} } }, 'other-person' => {'other-child' => {} } })
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37 hash_tree.visit_all {|node| puts node.node_name}