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43 lines
840 B
Plaintext
43 lines
840 B
Plaintext
# Basic iteration
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# Good ol' for-loop
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for i in [1, 2, 3]
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puts i
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end
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# Typically we don't use for-loops in Ruby, though.
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# Rubyists tend to prefer .each
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[1, 2, 3].each { |i| puts i }
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# Using .each looks neater and it allows for powerful chaining
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# of enumerable types.
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#
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# This example maps the array to [2, 4, 6] and prints each element.
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[1, 2, 3].map { |i| i * 2 }.each { |i| puts i }
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#
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# Another kind of loop with specified iterations
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10.times { puts 'test' }
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10.times do |n|
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puts "number #{n}"
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end
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# Conditionals
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if 1 == 0
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puts 'oh no'
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elsif 1 == 1
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puts "that's better"
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else
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puts 'cut it out'
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end
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# unless means 'if not'
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unless 1 == 0
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puts 'everything is ok'
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end
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# If the condition is short you can put it on one line.
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happiness = 0 if 'my life'.empty?
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# Or use ternary operator
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happiness = 'my life'.empty? ? 0 : 100
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