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I've been working on a project where I'm encoding numbers as characters. Being used to C++, I assumed I could just use any 8bit number and cast it to a character. However, python's chr() function is returning Unicode characters, which aren't 8-bit, so that will not work.

I am new to Python and, from what I've read, previous versions used to have 2 separate functions: chr() for ASCII characters and unichr() for Unicode characters.

I am also limited to what I can get in the standard python library for windows (we are not allowed to install modules with pip).

This might usually be okay, but here's an example of when this can mess with my program: If I'm encoding the integer 143:

# this is not taken from my actual code
num = 143    
c = chr(143)
print(c)

I would expect this to print the ASCII character (a capital A with a little circle above it). Instead, I get the unicode \x8f, which represents "SS3" (Single Shift 3).

TL;DR: I'm converting 8-bit numbers to characters, but chr() converts to Unicode and I REALLY need a way to convert to ASCII instead, but I can't seem to find it in the standard library.

I know that this is such a simple problem and it's extremely frustrating to be stuck on this of all things.

Thanks a lot in advance!
Have a nice day!
- Vlad

snakecharmerb
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Vlad2000Andrei
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    [ASCII](https://en.wikipedia.org/wiki/ASCII) is a ***7-bit*** encoding. And the hexadecimal representation of decimal `143` is `8f`. And what `8f` "means" depends on encoding. – Some programmer dude Mar 03 '20 at 08:05

1 Answers1

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"A with a little circle above it" is not an ASCII character, and 143 is outside the ASCII range (0-127).

It seems you are thinking in terms of the encoded bytes rather than unicode codepoints (which Python3 uses to represent string values). See here for 8 bit encodings where b'\x8f' represents 'Å‎'.

You probably want to do something like this:

import sys
c = 143
# Convert to byte
b = c.to_bytes(1, sys.byteorder)
# Decode to unicode (str) and print
print(b.decode('cp437'))
Å‎

You could also take a look at the struct package in the standard library, which deals with bytes and chars in a more "C-like" fashion.

snakecharmerb
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