resume()

The resume() function in Lua resumes a coroutine after it has been paused.

Syntax

The resume() function resumes a coroutine named routine.

coroutine.resume(routine)

Example

Consider the following code:

local routineX = coroutine.create(
  function ()
    for i = 1, 5, 1 do
      print("Run coroutineX!")
        if i == 2 then
          coroutine.yield()
        end
    end
  end
)

local routineY = coroutine.create(
  function ()
    for i = 1, 3, 1 do
      print("Run coroutineY!")
    end
  end
)

print("Coroutine resumed!")
coroutine.resume(routineX)

print("Coroutine resumed!")
coroutine.resume(routineY)

print("Coroutine resumed!")
coroutine.resume(routineX)

Two coroutines are created. routineX prints "Run coroutineX!" twice before stopping. routineY prints "Run coroutineY!" three times and ends. routineX then resumes and continues to print out the text three more times before ending.

This example results in the following output:

Coroutine resumed!
Run coroutineX!
Run coroutineX!
Coroutine resumed!
Run coroutineY!
Run coroutineY!
Run coroutineY!
Coroutine resumed!
Run coroutineX!
Run coroutineX!
Run coroutineX!

A real world example of using resume() is when copying and pasting a large folder into another folder or moving a large folder into another folder on the computer. The coroutine runs to move items to another folder, pauses to update the visual loading bar, and then resumes the coroutine of moving items over. And that cycle repeats over and over again until the entire transfer is complete.