I saw one example

int x = 10;
int y = 5;

bool isGreater = x > y;

printf("%d", isGreater);

But I could write this

int x = 10;
int y = 5;

printf("%d", x > y);

I am a complete beginner and I have no real reason why I would or would not want to deal with boolean variables, but I want to understand their raison d’être.

Edit: typo city

  • CameronDev
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    3 days ago

    Except that a lot of the cstdlib functions return an int, where 0 == success, and negative numbers are falsy.

    • hendrik@palaver.p3x.de
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      3 days ago

      The way I make sense of it, is we sometimes return failure (i.e. from main). So 0 is no failure (aka success) and we can use the same thinking. The correct, expressive way to write it is probably use “EXIT_SUCCESS” and skip the ones and zeros. Pretty sure this comes from Unix. And with a lot of the other functions in cstdlib it’s the same way as using integers as booleans. For example a “malloc()” will either return your memory or a null pointer and the 0 is the special failure case.

      But IMO the programming language shows its age and the context it was used in. More modern programming language design tends to be more strict with the types. Differentiate between interfacing with Unix stuff and other kinds of values. And we got more powerful concepts to deal with errors. So we don’t always have to abuse the zero to say we ended up in some special case.

      • CameronDev
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        3 days ago

        Malloc return 0 is a failure, but open return 0 is success. It’s just inconsistent, and it’s definitely an age and context thing.

        Rust’s Result api are a pretty great solution. Not sure what other options are out there though.

    • durinnOP
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      3 days ago

      But I think one has to keep apart return codes that are signals to the OS and the end user, and 1/0 in a true/false context in conditional statements.