yield, block and Benchmark

yield 和 call back 都可以像是把function, 一段code 當參數一樣丟進去
而benchmark則可以幫我們測量一下時間

require 'benchmark'

def yyield
    yield "a"
    yield "b"
 end


Benchmark.bm do |x|
  x.report {
    yyield do |k|
      puts k
    end
  }
end

def block(&block)
  block.call("a")
  block.call("b")
end

Benchmark.bm do |x|
  x.report {
    block do |k|
    puts k
    end
  }
end

第一次結果是
user system total real
a
b
0.000000 0.000000 0.000000 ( 0.000858)
user system total real
a
b
0.000000 0.000000 0.000000 ( 0.000231)

之後
user system total real
a
b
0.000000 0.000000 0.000000 ( 0.000030)
user system total real
a
b
0.000000 0.000000 0.000000 ( 0.000024)