How to convert a raw string r'\xdd' to '\xdd' more gracefully?

[Jach Feng]

Roel Schroeven 在 2022年12月7日 星期三下午4:42:48 [UTC+8] 的信中寫道：
> Op 7/12/2022 om 4:37 schreef Jach Feng:
> > MRAB 在 2022年12月7日 星期三上午11:04:43 [UTC+8] 的信中寫道： 
> > > On 2022-12-07 02:23, Jach Feng wrote: 
> > > > s0 = r'\x0a' 
> > > > At this moment it was done by 
> > > > 
> > > > def to1byte(matchobj): 
> > > > ....return chr(int('0x' + matchobj.group(1), 16)) 
> > > > s1 = re.sub(r'\\x([0-9a-fA-F]{2})', to1byte, s0) 
> > > > 
> > > > But, is it that difficult on doing this simple thing? 
> > > > 
> > > You could try this: 
> > > 
> > > >>> s0 = r'\x0a' 
> > > >>> ast.literal_eval('"%s"' % s0) 
> > > '\n' 
> > Not work in my system:-( 
> > 
> > Python 3.8.8 (tags/v3.8.8:024d805, Feb 19 2021, 13:08:11) [MSC v.1928 32 bit (Intel)] on win32 
> > Type "help", "copyright", "credits" or "license" for more information. 
> > >>> s0 = r'\x0a' 
> > >>> import ast 
> > >>> ast.literal_eval("%s" % s0) 
> > Traceback (most recent call last): 
> > File "<stdin>", line 1, in <module> 
> > File "C:\Users\Jach\AppData\Local\Programs\Python\Python38-32\lib\ast.py", line 59, in literal_eval 
> > node_or_string = parse(node_or_string, mode='eval') 
> > File "C:\Users\Jach\AppData\Local\Programs\Python\Python38-32\lib\ast.py", line 47, in parse 
> > return compile(source, filename, mode, flags, 
> > File "<unknown>", line 1 
> > \x0a 
> > ^ 
> > SyntaxError: unexpected character after line continuation character
> You missed a pair of quotes. They are easily overlooked but very 
> important. The point is to wrap your string in another pair of quotes so 
> it becomes a valid Python string literal in a Python string which can 
> then be passed to ast.literal_eval(). Works for me: 
> 
> In [7]: s0 = r'\x0a' 
> 
> In [8]: import ast 
> 
> In [9]: ast.literal_eval('"%s"' % s0) 
> Out[9]: '\n' 
> 
> -- 
> "Experience is that marvelous thing that enables you to recognize a 
> mistake when you make it again." 
> -- Franklin P. Jones
Thank you for notifying me. I did notice those  ''' in MRAB's post, but didn't figure out what it is at that time:-(