从变量打印原始字符串? (没有得到答案)

我试图找到一种从变量中打印原始形式的字符串的方法。例如,如果我在 Windows 中添加一个路径环境变量,它可能看起来像 'C:\\Windows\Users\alexb\',我知道我可以做到:

print(r'C:\\Windows\Users\alexb\')

但是我不能把 r放在变量前面... ... 例如:

test = 'C:\\Windows\Users\alexb\'
print(rtest)

显然只是想打印 rtest

我还知道

test = 'C:\\Windows\Users\alexb\'
print(repr(test))

但是这个返回 'C:\\Windows\\Users\x07lexb' 我也是

test = 'C:\\Windows\Users\alexb\'
print(test.encode('string-escape'))

因此,我想知道是否有任何优雅的方法,使一个变量保持路径打印 RAW,仍然使用测试?如果能公正一点就好了

print(raw(test))

但事实并非如此

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You can't turn an existing string "raw". The r prefix on literals is understood by the parser; it tells it to ignore escape sequences in the string. However, once a string literal has been parsed, there's no difference between a raw string and a "regular" one. If you have a string that contains a newline, for instance, there's no way to tell at runtime whether that newline came from the escape sequence \n, from a literal newline in a triple-quoted string (perhaps even a raw one!), from calling chr(10), by reading it from a file, or whatever else you might be able to come up with. The actual string object constructed from any of those methods looks the same.

I had a similar problem and stumbled upon this question, and know thanks to Nick Olson-Harris' answer that the solution lies with changing the string.

Two ways of solving it:

  1. Get the path you want using native python functions, e.g.:

    test = os.getcwd() # In case the path in question is your current directory
    print(repr(test))
    

    This makes it platform independent and it now works with .encode. If this is an option for you, it's the more elegant solution.

  2. If your string is not a path, define it in a way compatible with python strings, in this case by escaping your backslashes:

    test = 'C:\\Windows\\Users\\alexb\\'
    print(repr(test))
    

Get rid of the escape characters before storing or manipulating the raw string:

You could change any backslashes of the path '\' to forward slashes '/' before storing them in a variable. The forward slashes don't need to be escaped:

>>> mypath = os.getcwd().replace('\\','/')
>>> os.path.exists(mypath)
True
>>>

Your particular string won't work as typed because of the escape characters at the end \", won't allow it to close on the quotation.

Maybe I'm just wrong on that one because I'm still very new to python so if so please correct me but, changing it slightly to adjust for that, the repr() function will do the job of reproducing any string stored in a variable as a raw string.

You can do it two ways:

>>>print("C:\\Windows\Users\alexb\\")


C:\Windows\Users\alexb\


>>>print(r"C:\\Windows\Users\alexb\\")
C:\\Windows\Users\alexb\\

Store it in a variable:

test = "C:\\Windows\Users\alexb\\"

Use repr():

>>>print(repr(test))
'C:\\Windows\Users\alexb\\'

or string replacement with %r

print("%r" %test)
'C:\\Windows\Users\alexb\\'

The string will be reproduced with single quotes though so you would need to strip those off afterwards.

In general, to make a raw string out of a string variable, I use this:

string = "C:\\Windows\Users\alexb"


raw_string = r"{}".format(string)

output:

'C:\\\\Windows\\Users\\alexb'

I know i'm too late for the answer but for people reading this I found a much easier way for doing it

myVariable = 'This string is supposed to be raw \'
print(r'%s' %myVariable)

Just simply use r'string'. Hope this will help you as I see you haven't got your expected answer yet:

    test = 'C:\\Windows\Users\alexb\'
rawtest = r'%s' %test

I have my variable assigned to big complex pattern string for using with re module and it is concatenated with few other strings and in the end I want to print it then copy and check on regex101.com. But when I print it in the interactive mode I get double slash - '\\w' as @Jimmynoarms said:

The Solution for python 3x:

print(r'%s' % your_variable_pattern_str)

Replace back-slash with forward-slash using one of the below:

  • re.sub(r"\", "/", x)
  • re.sub(r"\", "/", x)

i wrote a small function.. but works for me

def conv(strng):
k=strng
k=k.replace('\a','\\a')
k=k.replace('\b','\\b')
k=k.replace('\f','\\f')
k=k.replace('\n','\\n')
k=k.replace('\r','\\r')
k=k.replace('\t','\\t')
k=k.replace('\v','\\v')
return k

try this. Based on what type of output you want. sometime you may not need single quote around printed string.

test = "qweqwe\n1212as\t121\\2asas"
print(repr(test)) # output: 'qweqwe\n1212as\t121\\2asas'
print( repr(test).strip("'"))  # output: qweqwe\n1212as\t121\\2asas

Here is a straightforward solution.

address = 'C:\Windows\Users\local'
directory ="r'"+ address +"'"

print(directory)

"r'C:\\Windows\\Users\\local'"

This does the trick

>>> repr(string)[1:-1]

Here is the proof

>>> repr("\n")[1:-1] == r"\n"
True

And it can be easily extrapolated into a function if need be

>>> raw = lambda string: repr(string)[1:-1]
>>> raw("\n")
'\\n'

To turn a variable to raw str, just use

rf"{var}"

r is raw and f is f-str; put them together and boom it works.