最简单的通用字符串处理方法将在python2和python3中都有效,而不必使用six这样的第三方模块?
我可以使用if sys.version_info > (3, 0)...
很好,但无法想出一种方法来完全覆盖字符串方法以使字节间的编码/解码是透明的?
目标是找到可能的最少代码,以允许编写独立于版本的脚本(不依赖)。
six source code不太复杂,为什么不只将字符串部分复制到代码库中呢?这样,您便拥有了一种完善的统一字符串处理方法。即下面的代码应该做:
import sys
PY2 = sys.version_info[0] == 2
PY3 = sys.version_info[0] == 3
if PY3:
text_type = str
binary_type = bytes
else:
text_type = unicode
binary_type = str
def ensure_binary(s, encoding='utf-8', errors='strict'):
if isinstance(s, text_type):
return s.encode(encoding, errors)
elif isinstance(s, binary_type):
return s
else:
raise TypeError("not expecting type '%s'" % type(s))
def ensure_str(s, encoding='utf-8', errors='strict'):
if not isinstance(s, (text_type, binary_type)):
raise TypeError("not expecting type '%s'" % type(s))
if PY2 and isinstance(s, text_type):
s = s.encode(encoding, errors)
elif PY3 and isinstance(s, binary_type):
s = s.decode(encoding, errors)
return s
def ensure_text(s, encoding='utf-8', errors='strict'):
if isinstance(s, binary_type):
return s.decode(encoding, errors)
elif isinstance(s, text_type):
return s
else:
raise TypeError("not expecting type '%s'" % type(s))
在每个文件内,将此行添加到每个文件的顶部
PY3 = sys.version_info[0] == 3
if PY3:
from builtins import str as unicode