Method: Proc#to_trans

Defined in:
lib/coroutines/operators.rb

#to_trans ⇒ Object

:call-seq:

proc.to_trans -> transformer

Allows implicit conversion of Proc to Transformer. The transformer is a combination of map and filter over its input values: For each input value, proc is called with the input value as parameter. Every non-nil value returned by proc is yielded as an output value.

This is similar to Enumerable#map followed by Array#compact, but without constructing the intermediate Array (so it’s even more similar to something like enum.lazy.map(&proc).reject(&:nil?), using the lazy enumerator introduced in Ruby 2.0).

Example:

(1..10) >= proc{|x| x.to_s + ", " if x.even? } >= ""
# => "2, 4, 6, 8, 10, "



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# File 'lib/coroutines/operators.rb', line 119

def to_trans
	Transformer.new do |y|
		loop do
			value = self.call(y.await)
			y.yield value unless value.nil?
		end
	end
end