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For grabbing the CPU features, there is some rudimentary implementation for x86 here: https://github.com/c3lang/c3c/blob/master/lib/std/core/priva... but not properly tested (which is to say, I would not count on it to work properly).

The `@require` here is creating a contract. You can't give a padding that is 0xFF, that's a programming error. However, you might have data which is invalid – in that case the typical error is INVALID_CHARACTER. To pass in a too small buffer is a programming error since the output buffer must be calculated first, so that's why that is not an error either. This was a deliberate change to make the API tighter.

So it's quite possible to add an "INVALID_LENGTH" error, but that should only be there in case one does encryption / decryption where the length cannot be easily determined beforehand i.e. it's part of the unknown input which the function determines. But in the Base32 implementation this is not the case. Either use it with an allocator for it to allocate sufficient memory for the data, or calculate that the buffer you pass in is big enough (or run into asserts if it isn't)

1 comments

Oh thank you, that cpu_detect.c3 is exactly what I need, the posted single-header library is almost the same in terms of functionality.

BTW my last question still stands, however, that if there is a C library that is only a single header file that implements functions through macros, can it be used from C3? In C, for what I posted, you would need to first do "#define CPUDETECT_IMPL" and then include the header file. Could it be done from C3 somehow? As in, could this (or any) single-header library be used from C3?

And regarding the errors, can I have something like "Error" (in Odin), or an enum of errors? Sorry for this silly question, I realize I will have to read the source code of the libraries first.

Thank you for your help!

It is possible to use a single-header library as part of C3 libraries or your project. However, it must be noted that this will inhibit the ability to cross compile, as the compilation of the header is outsourced to the natively installed C compiler.

For that reason it's not an option for the standard library, but can certainly be useful for programs and libraries.

For faults, they are usually defined with `faultdef` which allows you to define one or more faults:

    faultdef SOMETHING_WENT_SIDEWAYS, BIG_OOPS;

Then you use them as if they were constants:

    if (x > 0) return BIG_OOPS?;

If they are defined in another module, say "foo::bar::baz", then:

    if (x > 0) return baz::BIG_OOPS?;

Using path shortening "foo::bar::baz::BIG_OOPS" would also be valid, but is not necessary nor recommended.

Thank you!

Is it possible to do something like:

  faultdef {
    FOO, // comment
    BAR, // another comment
    BAZ, // yadda
    // Maybe this would work, too (for docgen if available)
    QUX
  }

or something like that?

Does C3 have a way to generate documentation?

You could do

    faultdef
        FOO, // comment
        BAR, // comment
        QUX; // comment

There are third party tools to generate docs. You can also get some json output from the c3 compiler itself to base docs on