제어 흐름

코루틴

yield from 사용하기

제너레이터 gen()이 yield from subgen()이 직접 호출자를 이끌고, gen()은 subgen()이 종료될 때까지 실행을 중단한다.

def gen():
	for c in 'AB':
    	yield c
    for i in range(1,3):
    	yield 1
list(gen())

#위의 코드 단축

def gen():
	yield from 'AB'
    yield from range(1,3)
    
#, yield from으로 반복형 객체 연결하기
def chain(*iterables):
	for it in iterables:
    	yield from it
        
s = 'ABC'
t = tuple(range(3))
list(chain(s,t))

#yield from을 이용해서 averager()를 구동하고 보고서 생성

from collections import namedtuple

Result = namedtuple('Result','count average')

#하위
def averager():
	total = 0.0
    count = 0
    average = None
    while True:
    	term = yield
        if term is None:
        	break
        total += term
        count +=1
        average = total/count
   return Result(count, average)
 
 #대표
 def grouper(results, key):
 	while True:
    	results[key] = yield from averager()

#호출자
def main(data):
	results = {}
    for key, values in data.items():
    	group = grouper(results, key)
        next(group)
        for value in values:
        	group.send(value)
        group.send(None)
    
    return(results)

#실행 결과 보고서

def report(results):
	for key, result in sorted(results.items()):
    	group, unit = key.split(';')
        print('{:2} {:5} averaging {:.2f}{}'.format(
        		result.count,group,result.average,unit))