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Comment by uecker

19 days ago

why not std::string?

You can surely create a std::string-like type in C, call it "newstring", and write functions that accept and return newstrings, and re-implement the whole standard library to work with newstrings, from printf() onwards. But you'll never have the comfort of newstring literals. The nice syntax with quotes is tied to zero-terminated strings. Of course you can litter your code with preprocessor macros, but it's inelegant and brittle.

  • Because C wants to run on bare metal, an allocating type like C++ std::string (or Rust's String) isn't affordable for what you mean here.

    I think you want the string slice reference type, what C++ called std::string_view and Rust calls &str. This type is just two facts about some text, where it is in memory and how long it is (or equivalently where it ends, storing the length is often in practice slightly faster in real machines so if you're making a new one do that)

    In C++ this is maybe non-obvious because it took until 2020 for C++ to get this type - WG21 are crazy, but this is the type you actually want as a fundamental, not an allocating type like std::string.

    Alternatively, if you're not yet ready to accept that all text should use UTF-8 encoding, -- and maybe C isn't ready for that yet - you don't want this type you just want byte slice references, Rust's &[u8] or C++ std::span<char>

It's a class, so it doesn't work in C.

  • Sure, but you can have a similar string abstraction in C. What would you miss? The overloaded operators?

    • Automatic memory accounting — construct/copy/destruct. You can't abstract these in C. You always have to call i_copied_the_string(&string) after copying the string and you always have to call the_string_is_out_of_scope_now(&string) just before it goes out of scope

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