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rubycodeblocksproc

Why do these two methods give me two different times?

Both methods calculate the time it takes ruby to call and run a code block. I don't see any reason why these two methods should return different results.

methodone gives me: 1.000135157

methodtwo gives me: 1.000108267

I'm a noob, am I even doing this right? please let me know.

def methodone(a)
  start = Time.now 
  a.call
  result = Time.now - start
end

def methodtwo(a)
  start_time = Time.now
  a.call
  end_time = Time.now
  result = end_time - start_time
end 

a = Proc.new do {}
end

p methodone(a)
p methodtwo(a)
Solution

  • You shouldn't expect them to be exactly the same. There will always be something going on outside of the Ruby process that will impact performance. You should consider a margin of error of, say, 0.1%

    def time(&block)
  t = Time.now.to_f
  yield 
  t2 = Time.now.to_f 
  puts t2 - t 
end

50.times do 
  time do 
    Proc.new { }
  end
end