annotate 1-Ruby/arrays.rb @ 25:e26607247dd2

Add sample data from book
author IBBoard <dev@ibboard.co.uk>
date Fri, 20 Jan 2017 21:01:09 +0000
parents 8d46064c9afc
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1 #! /usr/bin/env ruby
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2
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3 animals = ['lions', 'tigers', 'bears']
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5 # Default "puts" for array is one element per line
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6 puts animals
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8 puts "Accessing undefined indexes gives nil" if animals[10] == nil
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9 puts "Negative indexes also work (like Python): -1 = #{animals[-1]}"
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10 puts "And you get slices/ranges: 1..2 = #{animals[1..2]}"
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11 puts "1..2 is even an object: #{(1..2).class}"
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12 puts "and indexers are methods: [1].methods.include?(:[]) = #{[1].methods.include?(:[])}"
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13 # Note: we're using v1.9+ syntax - previously it was "….include?('[]')"
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14 puts "as is assignment to an array! [1].methods.include?(:[]=) = #{[1].methods.include?(:[]=)}"
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15 puts ""
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16 puts "All funky non-ASCII methods for arrays:"
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17 [].methods.each do |method|
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18 if method !~ /[a-z]/
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19 puts method
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20 end
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21 end
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23 puts ""
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24 puts "Arrays are also stacks with push() and pop() methods!"