arguments for proc in ruby

I am trying to run this code. I am trying to pass arguments into inner proc but my code does not run because of this. What am I doing wrong?

def log (descriptionOfProc,proc)
  puts "I have started proc #{descriptionOfProc}"
  puts "#{descriptionOfProc} is finished, returning #{proc.call}"
end

inner=Proc.new do |x,y|
  x+y
end

middle=Proc.new do |x| 
  log("inner", inner[1, 2])
  "check2"
end

outer=Proc.new do |x| 
  log("middle", middle)
  "check3"
end

puts log("outer", outer)

Solution

When you call inner[1,2] inside middle proc, you're actually executing the function which will return a value 3 then the argument to log will be "inner", 3 and since 3 does not respond to call your script fails.

If you want to fix your script your middle proc should look something like this

middle=Proc.new do |x| 
  log("inner", -> { inner[1, 2] })
  "check2"
end

The reason your code was not working was because you were executing the function inner with []. You can execute a block in ruby in different ways .call, .yield, .(), []. As you can see, you were passing in the result of inner instead of the proc itself. By wrapping the call to inner[1,2] inside another block to be executed later inside log by doing proc.call, you delayed inner's execution.