Question

我遇到了麻烦修改脚本以便生产者和使用者之间共享的数据结构是2元组的列表而不是字符串列表我似乎无法弄清楚什么是错的。

   #!/usr/bin/env python 
   # demonstrate coroutines in Python 
    """
   +  implements a typical producer/consumer algorithm 
   +  the consumer is a subroutine and main() is the producer
   +  producer sends a job request to consumer; waits for consumer to receive it
   +  the consumer waits for job request, does job, waits again
   +  keywords: 
   +  yield waits on producer - passes argument to producer at handoff
   +  next() sends job to consumer w/o msg
   +  send() sends job to consumer with msg 
   """
   import sys 
   def printjob(name):
   name += " "
   sys.stdout.write(name)
   """
+  CONSUMER 
+  'yield stuff' passes stuff back to the producer; when control resumes a 
+  message (it may be empty) is available from the producer as the return 
+  value from yield; note: cannot remove everything from the list since
+  the dereference to jobs[i] in yield is invalid
"""
def consumer(jobs):
  i = -1
# as long as something is in the jobs list keep processing requests
  while jobs:
      i = (i + 1) % len(jobs)
      # yield passes control back to producer with the ith job name
      getRequest = yield jobs[i]    # waits for request from producer 
      if getRequest:    # if getRequest is not empty process it
          request,name,num = getRequest
          if request == "add":
              jobs.append(name)
              jobs.append(num)
              sys.stdout.write("\nADD ")
          elif request == "remove" and name in jobs:
              jobs.remove(name)
              buf = "\nREMOVE " + name + "\n"
              sys.stdout.write(buf) 
   print "\nNo jobs left to do!\n" 
def producer(jobs):
   con = consumer(jobs)                   # start the consumer 
   buf = "Initial job list (" + str(len(jobs)) + "): "
   sys.stdout.write(buf)
   for i in range(len(jobs)):
      printjob(con.next())            # next sends job to consumer w/ no msg  
   printjob(con.send(("add", "iron",44)))  # send sends job to consumer w/ msg
   sys.stdout.write("\n")
   for i in range(len(jobs)):
      printjob(con.next())
   con.send(("remove","fold",33))
   for i in range(len(jobs)):
      printjob(con.next()) 
   con.send(("remove","wash",11))
   for i in range(len(jobs)):
      printjob(con.next()) 
   print "\nProducer Done."
"""
+ MAIN 
+ acts as the producer coroutine
+ next passes a job to the consumer with no message passing
+ send passes a job to the consumer with a message 
"""
if __name__ == "__main__":             # this means initialize once only
   jobs = [("wash",11),("dry",22),("fold",33)]        # tuble list
   pro = producer(jobs)

非常感谢任何帮助！

Answer 1

我怀疑错误是指向这一行：

name += " "

...因为你（正如错误所说）试图将字符串" "连接到元组("wash",11)。你究竟想用这条线做什么？如果您只想打印一些字符串形式的元组，请使用str函数：

sys.stdout.write(str(name) + '\n')

python Traceback（最近一次调用最后一次）：＆amp; TypeError：只能将元组（不是＆＃34; str＆＃34;）连接到元组

1 个答案: