f-string error message not understood

[Skaperen]

i don't understand this error message

Output:
t2a/phil /home/phil 452> py py/cmd/lndir.py -v foo bar/a/b/c/x File "py/cmd/lndir.py", line 133 print(f'makedirs({dir!r},mode={mode!e}) todo{n}') ^ SyntaxError: f-string: invalid conversion character: expected 's', 'r', or 'a' lt2a/phil /home/phil 453>

my first thought was to check the line before it. i'm sure lots of you will beg for the code, since this is an open project, i can post it. so here it is:

#!/usr/bin/env python3 # -*- coding: utf-8 -*- from os import link,makedirs,mkdir from os.path import lexists,join,split from sys import argv,stderr modes = dict( # aliases for mode settings x = 0o0100, xx = 0o0110, xxx = 0o0111, r = 0o0400, rr = 0o0440, rrr = 0o0444, rx = 0o0500, rxx = 0o0510, rxxx = 0o0511, rxr = 0o0540, rxrx = 0o0550, rxrxx = 0o0551, rxrr = 0o0544, rxrxr = 0o0554, rxrxrx = 0o0555, rw = 0o0600, rwr = 0o0640, rwrr = 0o0644, rwrw = 0o0660, rwrww = 0o0662, rwrwr = 0o0664, rwrwrw = 0o0666, rwx = 0o0700, rwxx = 0o0710, rwxxx = 0o0711, rwxr = 0o0740, rwxrr = 0o0744, rwxrx = 0o0750, rwxrxx = 0o0751, rwxrxr = 0o0754, rwxrxrx = 0o0755, rwxrwx = 0o0770, rwxrwxx = 0o0771, rwxrwxr = 0o0774, rwxrwxrx = 0o0775, rwxrwxrwx = 0o0777, rwxrwxrwt = 0o1777, rwxrwsrwx = 0o2777, rwxrwsrwt = 0o3777, rwsrwxrwx = 0o4777, rwsrwxrwt = 0o5777, rwsrwsrwx = 0o6777, rwsrwsrwt = 0o7777, dir = 0o0750, read = 0o0400, write = 0o0600, public = 0o0444, private = 0o0400, ) def help(*args): if args: arg = args[0] return arg.lower() in ('-h','--help') print(' lndir [options] srcpath destdir') return 1 def version(*args): if args: arg = args[0] return arg.lower() in ('-v','--version') print(' lndir version 0.0.6') return 1 def main(args): parents = True verbose = False mode = None names = [] while args: arg = args.pop(0) if not arg: exit('error: empty argument in command line') elif arg[0] != '-': names.append(arg) elif arg in ('-','--'): break elif help(arg): help() version() exit(1) elif arg in ('-m' '--mode'): if not args: exit(f'error: missing argument for {arg}') mode = args.pop(0) if not mode: exit(f'error: empty argument for {arg}') elif arg.startswith('-m=') or arg.startswith('--mode='): mode = arg.split('=',1)[1] if not mode: exit(f'error: empty value in {arg}') elif arg in ('-np','--noparents'): parents = False elif arg in ('-v','--verbose'): verbose = True elif version(arg): version() exit(1) if len(names)!=2: exit(f'too {("many","few")[len(names)<2]} arguments, expect 2, got {len(names)}: {" ".join(args)!r}') src,dir = names par,base = split(src) dst = join(dir,base) if isinstance(mode,str): mode = mode.lower() if mode in modes: mode = modes[mode] try: mode = int(mode,8) except Exception: pass if isinstance(src,(bytes,bytearray)): src = ''.join(chr(x)for x in src) if isinstance(dir,(bytes,bytearray)): dir = ''.join(chr(x)for x in dir) for n in (0,1): try: print(f'link({src!r},{dst!r}) todo{n}') link(src,dst) print(f'link({src!r},{dst!r}) done{n}') except FileNotFoundError: if lexists(src): try: if isinstance(mode,int): print(f'makedirs({dir!r},mode={mode!e}) todo{n}') (makedirs if parents else mkdir)(dir,mode=mode) print(f'makedirs({dir!r},mode={mode!e}) done{n}') else: print(f'makedirs({dir!r}) todo{n}') (makedirs if parents else mkdir)(dir) print(f'makedirs({dir!r}) done{n}') except FileNotFoundError: exit(f'parent directory missing while creating directory {dir!r}') except NotADirectoryError: exit(f'parent directory not a directory while creating directory {dir!r}') except PermissionError: exit(f'permission error while creating directory {dir!r}') except OSError: exit(f'unknown error while creating directory {dir!r}') else: exit((f'{n} source file {src!r}' if lexists(dir) else f'target directory {dir!r}')+' not found') except FileExistsError: exit(f'target file {dst!r} exists') except NotADirectoryError: exit(f'target directory {dir!r} exists but is not a directory') except PermissionError: exit(f'target directory {dir!r} or source file {src!r} permission error') if verbose: print(f'{src!r} == {dst!r}',flush=True) return 0 if __name__ == '__main__': cmdpath = argv.pop(0) try: result = main(argv) except BrokenPipeError: exit(141) except KeyboardInterrupt: print(flush=True) exit(98) if isinstance(result,(bytes,bytearray)): result=''.join(chr(x)for x in result) if isinstance(result,str): print(result,file=stderr,flush=True) result=1 if result is None or result is True: result=0 elif result is False: result=1 exit(int(float(result)))

[bowlofred]

What are you intending with the {mode!e} in that string? e isn't a valid conversion (unless you add it yourself).

If you're trying to print the mode as octal, that would be {mode:o}.

>>> mode = 0o0444 >>> mode 292 >>> print(f"{mode:o}") 444

[Skaperen]

doh! that was the error. i misunderstood "conversion" because the "^" pointer is in the wrong position. it should have been "!r" (it could have the value None) ... an adjacent key typo.

[bowlofred]

What benefit do you get from changing that conversion then? Integers and None should print identically among all built-in conversions.

>>> print(f"{None} {None!r} {33} {33!r}") None None 33 33

[Skaperen]

probably no benefit in this case. my habits for adding temporary code to help debugging does not include thinking about the optimal choice of code since i will be removing it later.