This repo has a quick demo of a class implementing a queue which allows for a certain number of concurrently executing tasks. This is typically used to protect a resource that only allows a certain number of concurrent connections. Otherwise GCD is pretty good at managing active numbers of tasks on its own.
Running this application, you'll see:
Hello, World!printed to the console.- One hundred instances of
Task: Nprinted to the console in (by default) batches of five. Goodbye, World!as the program terminates.
As you've probably guessed, the maximum concurrency set up
in the demo in main.swift is five.