Idiomatic Python手记一: average in FP way

方法一:

1 import operator
2 
3 def average(*args):
4     return reduce(operator.add, args) / len(args) if args else 0

注释:

语句 if []: / if (): / if '' : / if {}: 对于以上空集逻辑值为 False
等同于 if len(list) == 0 : pass 等

方法二:

1 import functools
2 
3 def average(*args):
4     acc = functools.partial(reduce, lambda x, y : x + y)
5     # acc = functools.partial(reduce, operator.add)
6     return acc(args) / len(args) if args else 0

注释:

acc 为初值为lambda 表达式的reduce偏函数