updated threading example to use Event object instead of user defined Signal instance

ramalho · ramalho · commit d7e37ad0fdff · 2017-03-05T14:22:20.000-03:00
diff --git a/18-asyncio/spinner_thread.py b/18-asyncio/spinner_thread.py
@@ -11,19 +11,14 @@
 import sys
 
 
-class Signal: # <1>
- go = True
-
-
-def spin(msg, signal): # <2>
+def spin(msg, done): # <2>
 write, flush = sys.stdout.write, sys.stdout.flush
 for char in itertools.cycle('|/-\\'): # <3>
 status = char + ' ' + msg
 write(status)
 flush()
 write('\x08' * len(status)) # <4>
- time.sleep(.1)
- if not signal.go: # <5>
+ if done.wait(.1): # <5>
 break
 write(' ' * len(status) + '\x08' * len(status)) # <6>
 
@@ -35,13 +30,13 @@ def slow_function(): # <7>
 
 
 def supervisor(): # <9>
- signal = Signal()
+ done = threading.Event()
 spinner = threading.Thread(target=spin,
- args=('thinking!', signal))
+ args=('thinking!', done))
 print('spinner object:', spinner) # <10>
 spinner.start() # <11>
 result = slow_function() # <12>
- signal.go = False # <13>
+ done.set() # <13>
 spinner.join() # <14>
 return result
 
diff --git a/18b-async-await/spinner_thread.py b/18b-async-await/spinner_thread.py
@@ -11,19 +11,14 @@
 import sys
 
 
-class Signal: # <1>
- go = True
-
-
-def spin(msg, signal): # <2>
+def spin(msg, done): # <2>
 write, flush = sys.stdout.write, sys.stdout.flush
 for char in itertools.cycle('|/-\\'): # <3>
 status = char + ' ' + msg
 write(status)
 flush()
 write('\x08' * len(status)) # <4>
- time.sleep(.1)
- if not signal.go: # <5>
+ if done.wait(.1): # <5>
 break
 write(' ' * len(status) + '\x08' * len(status)) # <6>
 
@@ -35,13 +30,13 @@ def slow_function(): # <7>
 
 
 def supervisor(): # <9>
- signal = Signal()
+ done = threading.Event()
 spinner = threading.Thread(target=spin,
- args=('thinking!', signal))
+ args=('thinking!', done))
 print('spinner object:', spinner) # <10>
 spinner.start() # <11>
 result = slow_function() # <12>
- signal.go = False # <13>
+ done.set() # <13>
 spinner.join() # <14>
 return result
 

-Original file line number
+Diff line change
 importsys
 -classSignal: # <1>
 -go=True
+-
+-
 -defspin(msg, signal): # <2>
 +defspin(msg, done): # <2>
 write, flush=sys.stdout.write, sys.stdout.flush
 forcharinitertools.cycle('|/-\\'): # <3>
 status=char+' '+msg
 write(status)
 flush()
 write('\x08'*len(status)) # <4>
 -time.sleep(.1)
 -ifnotsignal.go: # <5>
 +ifdone.wait(.1): # <5>
 break
 write(' '*len(status) +'\x08'*len(status)) # <6>
 defsupervisor(): # <9>
 -signal=Signal()
 +done=threading.Event()
 spinner=threading.Thread(target=spin,
 -args=('thinking!', signal))
 +args=('thinking!', done))
 print('spinner object:', spinner) # <10>
 spinner.start() # <11>
 result=slow_function() # <12>
 -signal.go=False# <13>
 +done.set()# <13>
 spinner.join() # <14>
 returnresult