Add thread_pool_patterns

thread_pool_patterns/submit_use_callback.py

@@ -0,0 +1,45 @@
+#!/usr/bin/env python3
+import timeit
+from time import sleep
+from random import randint
+from concurrent.futures import ThreadPoolExecutor, Future
+
+results: list[int] = []
+
+def add_one(number: int) -> int:
+    sleep(randint(0,2))
+    result = number + 1
+    return result
+
+
+def aggregate_results(future: Future):
+    results.append(future.result())
+
+
+def first_method():
+    with ThreadPoolExecutor(32) as executor:
+        futures = [executor.submit(add_one, number) for number in range(10)]
+        for future in futures:
+            future.add_done_callback(aggregate_results)
+
+
+def second_method():
+    futures = []
+    with ThreadPoolExecutor(32) as executor:
+        for number in range(10):
+            futures.append(executor.submit(add_one, number))
+            futures[-1].add_done_callback(aggregate_results)
+
+
+def main():
+    print(timeit.timeit(first_method, number=1))
+    print(results)
+    print("All done!\n")
+    results.clear()
+    print(timeit.timeit(second_method, number=1))
+    print(results)
+    print("All done!")
+
+
+if __name__ == "__main__":
+    main()