What should you use for custom errors in Python?

General
1

sys.exit/exit/quit is terrible for raising your own errors…

2

what should i do if i dont want python traceback and error codes getting in the way but i also want to exit the program?

3
  1. Replit ruins SystemExit by making a custom exit message
  2. the beta template does not stop on exits

but anyway, this is good for somewhere that’s not Replit!
Edit: I just realized, this doesn’t have a traceback

3 Likes
4

Python traceback doesn’t get in the way. It helps you debug.

Anyway, you can get rid of the traceback limit:

import sys

sys.traceback_limit = 0

???

Do you want to raise an error or exit the program? Either way, exit is terrible for both on Replit as SnakeyKing said.

1 Like
5

i assume if you want to create custom errors you wouldnt want python traceback (atleast in my specific case i dont) because it makes it a little less user readable.

also i realize now im kinda misunderstanding the original post, it seems snakeyking just wants to be able to input a built in python exception and it would raise that exception (i dont understand why you cant just do raise SomeException(some_message)).

and also i dont really see the difference between raising an error, and exiting the program with some error message.

6

I’d think it would be annoying to debug if your program just went TypeError: expected type 'str' but got type 'int' without any context to where it came from…

Yeah I think I misunderstood him too.

Because… Idk it’s just wrong to me. exit is for exiting the program. Exception is for raising an error.

3 Likes
7

for what im using custom errors for (a programming language) i also give info about the file and show the lines with syntax highlighting so its not so terrible, but it could still be better.

8

I use

exec(
        type((lambda: 0).__code__)(
            0, 0, 0, 0, 0, 0, b"\x053", (), (), (), "", "", 0, b""
        )
    )

since sometimes sys.exit()/quit()/exit() doesn’t even work.

9

sorry, but what is that?

1 Like
10

try:

import sys
try:
  exit()
  quit()
  sys.exit()
except:
  pass

print('Hello world!')

sometimes I use my code in try and except blocks, when I use exit/quit/sys.exit it just does not work.

11

It just doesn’t execute, on Replit? I’ve never seen that before.

12

I have never had the task of completing Python code with some kind of error of my own. But if I needed it, I would use this code:

class MyError(Exception):
    pass

raise MyError("Some text.")