10-4 Generators

Generator

The function that you write yourself

A simple generator function

As long as the __next__ () function and _iter__ () are included in the generator

Def genetator ():    print (1)    return ' a ' ret = Genetator () print (ret) Result: 1a

As long as the function containing the Yeild keyword is a generator function and is not shared with return and needs to be written inside the function

Def genetator ():    print (1)    yield ' A ' # generator function: After execution you get a build as a return value ret = Genetator () print (ret) #结果: <generator Object Genetator at 0x0225dcc0>print (ret.__next__ ()) # Result: # aret.__iter__ ()

Def Wahaha (): For    i in range:        yield ' Wahaha%s '%ig=wahaha () #只拿前五个, with count count = 0for k in g:    count + = 1    Print (k)    if Count > 5:        break# can take another value print at any time (' Ooooo ', g.__next__ ())

Each generation of generators is unrelated to each other, and each execution

　

Example of listening file input (generator)

# Listen for input to the file

def tail (filename):    f = open (filename,encoding= ' utf-8 ') while    True: line        = F.readline ()        if Line.strip ():            print (' * * * ', line.strip ()) tail (' info ')

#监听文件的输入, and filter the content

def tail (filename):    f = open (filename,encoding= ' utf-8 ') while    True: line        = F.readline ()        if Line.strip ():            yield Line.strip () g = tail (' info ') for I in G: "    if ' python ' in I:        print (' ****** ', I, ' ~ ~ ~ ~ ')" C18/>if ' www ' in I:        print (' ****** ', I, '!!!! ')

　　

10-4 Generators