35 lines
770 B
Ruby
35 lines
770 B
Ruby
#
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# shuffle.rb
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#
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module Puppet::Parser::Functions
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newfunction(:shuffle, :type => :rvalue, :doc => <<-EOS
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EOS
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) do |arguments|
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raise(Puppet::ParseError, "shuffle(): Wrong number of arguments " +
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"given (#{arguments.size} for 1)") if arguments.size < 1
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array = arguments[0]
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if not array.is_a?(Array)
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raise(Puppet::ParseError, 'shuffle(): Requires an array to work with')
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end
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return [] if array.size == 0
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return array if array.size <= 1
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list = array.clone
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elements = list.size
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# Simple implementation of Fisher–Yates in-place shuffle ...
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elements.times do |i|
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j = rand(elements - i) + i
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list[j], list[i] = list[i], list[j]
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end
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return list
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end
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end
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# vim: set ts=2 sw=2 et :
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