python正则表达式删除评论

Question

我将如何编写一个正则表达式来删除所有以＃开头并在该行结束处停止的注释-但同时要排除前两行，即

#!/usr/bin/python

和

#-*- coding: utf-8 -*-

Answer 1

您可以通过使用解析Python代码来删除注释tokenize.generate_tokens。以下是从docs对该示例进行的稍微修改的版本：

import tokenize
import io
import sys
if sys.version_info[0] == 3:
    StringIO = io.StringIO
else:
    StringIO = io.BytesIO

def nocomment(s):
    result = []
    g = tokenize.generate_tokens(StringIO(s).readline)  
    for toknum, tokval, _, _, _  in g:
        # print(toknum,tokval)
        if toknum != tokenize.COMMENT:
            result.append((toknum, tokval))
    return tokenize.untokenize(result)

with open('script.py','r') as f:
    content=f.read()

print(nocomment(content))

例如：

如果script.py包含

def foo(): # Remove this comment
    ''' But do not remove this #1 docstring 
    '''
    # Another comment
    pass

然后的输出nocomment是

def foo ():
    ''' But do not remove this #1 docstring 
    '''

    pass