method
tap
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tap()
public
Yields x to the block, and then returns x. 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.inspect}"} .to_a .tap {|x| puts "array: #{x.inspect}"} .select {|x| x%2==0} .tap {|x| puts "evens: #{x.inspect}"} .map { |x| x*x } .tap {|x| puts "squares: #{x.inspect}"}