method
tap
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tap()
public
Yields self to the block, and then returns self. The primary purpose of this method is to “tap into” a method chain, in order to perform operations on intermediate results within the chain.
(1..10) .tap {|x| puts "original: #{x}" } .to_a .tap {|x| puts "array: #{x}" } .select {|x| x.even? } .tap {|x| puts "evens: #{x}" } .map {|x| x*x } .tap {|x| puts "squares: #{x}" }