python r string for variable - Printable Version

python r string for variable - Printable Version

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python r string for variable - mg24 - Oct-28-2022

Hi Team,

how to apply r(raw string) for a variable path
r"\\IND200300400.XXX.XXXX.XXX\Recon Project\output1" ---------here directly attached r its ok.

folderpath = \\IND200300400.XXX.XXXX.XXX\
path = r(folderpath)?...... how to apply r for variable. if user pass variable.

def createfolder(folderpath,site):

    Constant_folder = r{folderpath}
    Constant_folder = r(folderpath)


    path = f"{Constant_folder}\{site}"
    try:
        os.makedirs(path, exist_ok=True)
        print("Directory '%s' created successfully" % path)
    except OSError as error:
        print("Directory '%s' can not be created")



if __name__ == "__main__":
    folderpath =  "\\IND200300400.XXX.XXXX.XXX\Recon Project\output1"
    site = "US"
    createfolder(folderpath, site)

RE: python r string for variable - deanhystad - Oct-28-2022

raw is only a thing for string literals. Normally when Python encounters a string while "compiling" your program, it replaces escape sequences with the actual un-printable character. The "r" prefix before a string literal tells Python to not look for escape sequences when making the str object. After the program compile stage, "raw" strings are not a thing anymore. All str objects are essentially "raw" strings, because none of them contain escape sequences.

if __name__ == "__main__":
    folderpath =  r"\\IND200300400.XXX.XXXX.XXX\Recon Project\output1"    # <- The "r" belongs here
    site = "US"
    createfolder(folderpath, site)

RE: python r string for variable - mg24 - Oct-28-2022

Hi deanhystad,

I am accepting folderpath from commandline.
python test1.py "\\IND200300400.XXX.XXXX.XXX\Recon Project\output1"

folderpath = sys.argv[1]

folderpath = r{folderpath } something like this.

thanks
mg

RE: python r string for variable - deanhystad - Oct-28-2022

If it is coming from the command line than it is already a str object and not a str literal. raw does not apply.

I did a little experiment. I wrote a program to spit out the command line argument

import sys
print(f"{sys.argv[1]}, {repr(sys.argv[1])}, {len(sys.argv[1])}"

I ran the program as "python text.py "\\\n". This was the output.

Output:
\\\n, '\\\\\\n', 4

The repr version of the command line argument looks odd, but the length shows this is an artifact of repr trying to show you that the string really contains "\\" and "\n" and not escape<\> and escape<n>.

If backslashes are giving you headaches, use forward slashes. Windows accepts forward slash as a path seperator.