本文不是介绍yield的使用的,仅仅是介绍yield和yield from两者区别的。
如果直接说两者的区别,估计不太明白,下面使用一个用例来说明两者之间的区别
def gen(*args, **kwargs):
for item in args:
yield item
def gen2(*args, **kwargs):
for item in args:
yield from item
if __name__ == '__main__':
astr = "ABC"
alist = [1, 2, 3]
adict = {"nba": "湖人", "age": 18}
# generate
agen = (i for i in range(4, 8))
new_list = gen(astr, alist, adict, agen)
new_list2 = gen2(astr, alist, adict, agen)
print(list(new_list))
print(list(new_list2))
结果如下:
['ABC', [1, 2, 3], {'nba': '湖人', 'age': 18}, <generator object <genexpr> at 0x108192990>]
['A', 'B', 'C', 1, 2, 3, 'nba', 'age', 4, 5, 6, 7]
结论:
yield和yield from后边加上可迭代对象的时候,yield from是将可迭代对象中的元素一个一个yield出来,而yield是直接yield的是可迭代对象
原文:https://www.cnblogs.com/suxianglun/p/10834611.html