浅析Python多线程下的变量问题

def process_student(name):
  std = Student(name)
  # std是局部变量，但是每个函数都要用它，因此必须传进去：
  do_task_1(std)
  do_task_2(std)

def do_task_1(std):
  do_subtask_1(std)
  do_subtask_2(std)

def do_task_2(std):
  do_subtask_2(std)
  do_subtask_2(std)

global_dict = {}

def std_thread(name):
  std = Student(name)
  # 把std放到全局变量global_dict中：
  global_dict[threading.current_thread()] = std
  do_task_1()
  do_task_2()

def do_task_1():
  # 不传入std，而是根据当前线程查找：
  std = global_dict[threading.current_thread()]
  ...

def do_task_2():
  # 任何函数都可以查找出当前线程的std变量：
  std = global_dict[threading.current_thread()]
  ...

import threading

# 创建全局ThreadLocal对象:
local_school = threading.local()

def process_student():
  print 'Hello, %s (in %s)' % (local_school.student, threading.current_thread().name)

def process_thread(name):
  # 绑定ThreadLocal的student:
  local_school.student = name
  process_student()

t1 = threading.Thread(target= process_thread, args=('Alice',), name='Thread-A')
t2 = threading.Thread(target= process_thread, args=('Bob',), name='Thread-B')
t1.start()
t2.start()
t1.join()
t2.join()

Hello, Alice (in Thread-A)
Hello, Bob (in Thread-B)