63 lines
1.3 KiB
Python
63 lines
1.3 KiB
Python
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#!/usr/bin/env python
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# -*- encoding: utf-8 -*-
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"""
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Topic: 带状态值的回调函数
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Desc :
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"""
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def apply_async(func, args, *, callback):
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# Compute the result
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result = func(*args)
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# Invoke the callback with the result
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callback(result)
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def add(x, y):
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return x + y
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# 类方案
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class ResultHandler:
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def __init__(self):
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self.sequence = 0
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def handler(self, result):
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self.sequence += 1
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print('[{}] Got: {}'.format(self.sequence, result))
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r = ResultHandler()
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apply_async(add, (2, 3), callback=r.handler)
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apply_async(add, ('hello', 'world'), callback=r.handler)
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# 闭包方案
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def make_handler():
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sequence = 0
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def handler(result):
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nonlocal sequence
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sequence += 1
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print('[{}] Got: {}'.format(sequence, result))
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return handler
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handler = make_handler()
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apply_async(add, (2, 3), callback=handler)
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apply_async(add, ('hello', 'world'), callback=handler)
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# 协程方案
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def make_handler():
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sequence = 0
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while True:
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result = yield
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sequence += 1
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print('[{}] Got: {}'.format(sequence, result))
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handler = make_handler()
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next(handler) # Advance to the yield
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apply_async(add, (2, 3), callback=handler.send)
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apply_async(add, ('hello', 'world'), callback=handler.send)
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