给定下面的例子,哪个更pythonic?使用函数组合、lambdas 或(现在)完全不同的东西?我不得不说 lambdas 似乎更具可读性,但 Guido 本人似乎想完全删除 lambdas - http://www.artima.com/weblogs/viewpost.jsp?thread=98196
from functools import partial
from operator import not_, ge
def get_sql_data_type_from_string(s):
s = str(s)
# compose(*fs) -> returns composition of functions fs
# iserror(f, x) -> returns True if Exception thrown from f(x), False otherwise
# Using function composition
predicates = (
('int', compose(not_, partial(iserror, int))),
('float', compose(not_, partial(iserror, float))),
('char', compose(partial(ge, 1), len)))
# Using lambdas
predicates = (
('int', lambda x: not iserror(int, x)),
('float', lambda x: not iserror(float, x)),
('char', lambda x: len(x) <= 1))
# Test each predicate
for i, (t, p) in enumerate(predicates):
if p(s):
return i, t
# If all predicates fail
return (i + 1), 'varchar'