# the function that will extract shared global variables
def extract(globals_dict: Dict[str, Any]) -> Dict[str, Any]:
return {'a': globals_dict['a']} # extract a
# the function that will merge shared global variables
def merge(old_globals: Dict[str, Any], new_globals: Dict[str, Any]) -> None:
old_globals.update(new_globals) # simply overwrite the old globals
# 'a' before update
print("global 'a' was", a)
print()
# spawn a snakefish thread and join it
t = snakefish.Thread(f, extract, merge)
print("thread alive?", t.is_alive())
t.start()
print("thread alive?", t.is_alive())
t.join()
print("thread alive?", t.is_alive())
print()
# check exit status and get the return value
assert (t.get_exit_status() == 0)
print("thread exit status:", t.get_exit_status())
print("result of f():", t.get_result())
print("global 'a' is", a) # 'a' after update
# release resources
t.dispose()
# blocking receive
print("thread #3: receiving an object...")
received2 = channel.receive_pyobj(True)
print("thread #3: timestamps are %s and %s" % (received1[0], received2[0]))
if received1[0] <= received2[0]:
print("thread #3: %s occurred before %s" %
(received1[1], received2[1]))
else:
print("thread #3: %s occurred before %s" %
(received2[1], received1[1]))
# spawn 3 snakefish threads
t1 = snakefish.Thread(f1)
t2 = snakefish.Thread(f2)
t3 = snakefish.Thread(f3)
t1.start()
t2.start()
t3.start()
# join the threads and check exit status
t1.join()
assert (t1.get_exit_status() == 0)
print("thread #1 exit status:", t1.get_exit_status())
print("result of f1():", t1.get_result())
t2.join()
assert (t2.get_exit_status() == 0)
import time
from typing import * # use type hints to make signatures clear
import snakefish
# the function that will be executed on a snakefish thread
def f() -> List[int]:
print("f() will sleep for 500 ms")
time.sleep(0.5)
return [i for i in range(200)] # return a large list
# spawn a snakefish thread
t = snakefish.Thread(f)
t.start()
# try to join the thread and time it
start = time.time()
while True:
if t.try_join():
print("try_join() successful")
break
else:
print("try_join() unsuccessful, sleep for 100ms")
time.sleep(0.1)
print("try_join() took %s sec" % (time.time() - start))
# check exit status and get the return value
assert (t.get_exit_status() == 0)
print("thread exit status:", t.get_exit_status())