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module Kernel
# call-seq:
# obj.yield_self {|_obj|...} -> an_object
# obj.then {|_obj|...} -> an_object
#
# Yields <i>obj</i> and returns the result.
#
# 'my string'.yield_self {|s|s.upcase} #=> "MY STRING"
#
def yield_self(&block)
return to_enum :yield_self unless block
block.call(self)
end
alias then yield_self
##
# call-seq:
# obj.tap{|x|...} -> obj
#
# Yields <code>x</code> to the block, and then returns <code>x</code>.
# 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}"}
#
def tap
yield self
self
end
end
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