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reduce-i.yaml
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--- !ruby/object:RI::MethodDescription aliases: [] block_params: comment: - !ruby/struct:SM::Flow::VERB body: " enum.reduce(initial, sym) => obj\n enum.reduce(sym) => obj\n enum.reduce(initial) {| memo, obj | block } => obj\n enum.reduce {| memo, obj | block } => obj\n" - !ruby/struct:SM::Flow::P body: Combines all elements of <em>enum</em> by applying a binary operation, specified by a block or a symbol that names a method or operator. - !ruby/struct:SM::Flow::P body: If you specify a block, then for each element in <em>enum<i> the block is passed an accumulator value (<i>memo</em>) and the element. If you specify a symbol instead, then each element in the collection will be passed to the named method of <em>memo</em>. In either case, the result becomes the new value for <em>memo</em>. At the end of the iteration, the final value of <em>memo</em> is the return value fo the method. - !ruby/struct:SM::Flow::P body: If you do not explicitly specify an <em>initial</em> value for <em>memo</em>, then uses the first element of collection is used as the initial value of <em>memo</em>. - !ruby/struct:SM::Flow::P body: "Examples:" - !ruby/struct:SM::Flow::VERB body: " # Sum some numbers\n (5..10).reduce(:+) #=> 45\n # Same using a block and inject\n (5..10).inject {|sum, n| sum + n } #=> 45\n # Multiply some numbers\n (5..10).reduce(1, :*) #=> 151200\n # Same using a block\n (5..10).inject(1) {|product, n| product * n } #=> 151200\n # find the longest word\n longest = %w{ cat sheep bear }.inject do |memo,word|\n memo.length > word.length ? memo : word\n end\n longest #=> "sheep"\n" full_name: Enumerable#reduce is_singleton: false name: reduce params: | enum.inject(initial, sym) => obj enum.inject(sym) => obj enum.inject(initial) {| memo, obj | block } => obj enum.inject {| memo, obj | block } => obj visibility: public