... "yield from" is available since Python 3.3! Python (programming language) Return sends a specified value back to its caller whereas Yield can produce a sequence of values. As in any programming language if we execute a function and it needs to perform some task and have to give its result so … Python使用yield和send的用法. When the function gets suspended, the state of that function is saved, this includes data like any variable bindings, the instruction pointer, the internal stack, and any exception handling. So, The “send” method works just like “next”, except that you can pass any Python … The yield from < expr > statement can be used inside the body of a generator. Until next time, happy coding. In effect, a yield-expression is like an inverted function call; the argument to yield is in fact returned (yielded) from the currently executing function, and the return value of yield is the argument passed in via send… The send() method returns the next value yielded by the generator, or raises StopIteration if the generator exits without yielding another value. Performing a file-system search, a user would be happier to receive results on-the-fly, rather the wait for a search engine to go through … Answer: From the “send” method, which can be invoked in place of the “next” function. When the Python yield statement is hit, the program suspends the function execution and returns the yielded value to the caller. To use the send method, the generator must wait for a yield statement so that the data sent can be processed or assigned to the variable on the left. This means that “yield” must be providing a value to the generator. Output: 1 2 3. When you're using send to "start" a generator (that is, execute the code from the first line of the generator function up to the first yield statement), you must send None. When the caller executes R = m.send(a), it puts the object a into the generator's input slot, transfers control to the generator, and waits for a response. Using the Python "yield" keyword A good example is a search task, where typically there is no need to wait for all results to be found. Where is it getting that value from? There’s also an async version, although this one has to be awaited. 先看一段普通的计算斐波那契续列的代码： 基本版： def old_fib(n): res = [0] * n index = 0 a = 0 b = 1 while index