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Ruby Ruby Blocks Working With Blocks Block Method Practice: Custom Classes

Rob Munoz
PLUS
Rob Munoz
Courses Plus Student 586 Points

Pass Blocks as Args

Hi, I'm struggling to complete this exercise. I was wondering if anybody could elaborate on how I might pass either M or J as an argument.

simple_benchmarker.rb
class SimpleBenchmarker
  def run(description, &block)
    start_time = Time.now
    block.call
    end_time = Time.now
    elapsed = end_time - start_time

    puts "\n#{description} results"
    puts "Elapsed time: #{elapsed} seconds"
  end
end

benchmarker = SimpleBenchmarker.new 

def M
  puts "abcd"
end

J = [1,2,3,4,5].each {|x| puts x}

benchmarker.run ("a string", J)

3 Answers

Hi Rob,

You will find two arguments inside def run on second line, you may notice.

First is description and second is &block

  def run(description, &block)

Call the run method on the benchmarker object and pass it two arguments. The first argument should be a string of the description. The second argument can be a block with any code you choose.

#First argument should have "string of description"
benchmarker.run "Any description you want" do

#Second argument should have anything in block
  10.times do
    puts "any code you choose"
  end

end

Here's fully explanation, let's look at 5:14

Please remember, don't add any extra codes and just follow the questions in order to pass the exercise.

Hope that helps. ;)

Hi Rob,

In your code, neither M or J are blocks. M is a method, and J is an array which was generated with the help of a block.

As it turns out, blocks cannot be stored directly in variables, so you will need to directly include a block along with your call to the run method. The syntax for that, as noted by Salmon, is:

benchmarker.run "Any description" do
 # anything here is inside your new block
end
Rob Munoz
PLUS
Rob Munoz
Courses Plus Student 586 Points

Awesome, thanks so much to the both of you. I still don't quite understand the methodology or syntax of passing a block but I made my own example and it worked. I guess I'm a sucker for parentheses. Some of the visual structure is lost when you don't delimit a second argument by a comma or contain it within a parentheses.