Comment by teo_zero

19 days ago

I agree on the former two (std::string and smart pointers) because they can't be nicely implemented without some help from the language itself.

The latter two (hash maps and vectors), though, are just compound data types that can be built on top of standard C. All it would need is to agree on a new common library, more modern than the one designed in the 70s.

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teo_zero

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ninkendo  19 days ago

I think a vec is important for the same reason a string is… because being able to properly get the length, and standardized ways to push/pop from them that don’t require manual bounds checking and calls to realloc.

Hash maps are mostly only important because everyone ought to standardize on a way of hashing keys.

But I suppose they can both be “bring your own”… to me it’s more that these types are so fundamental and so “table stakes” that having one base implementation of them guaranteed by the language’s standard lib is important.

uecker  19 days ago

why not std::string?

  • teo_zero  19 days ago

    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.

    • tialaramex  18 days ago

      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>