Luna/libluna/include/luna/Format.h

#pragma once
#include <luna/Attributes.h>
#include <luna/Result.h>
#include <stdarg.h>

typedef Result<void> (*callback_t)(char, void*);

// Format output according to a format string and a list of variadic arguments. callback is called with arg for every
// character in the resulting string.
Result<usize> cstyle_format(const char* format, callback_t callback, void* arg, va_list ap);

// Convenience function which outputs into a fixed-size buffer (not unlike vsnprintf)
usize vstring_format(char* buf, usize max, const char* format, va_list ap);

// Convenience function which outputs into a fixed-size buffer (not unlike snprintf)
usize string_format(char* buf, usize max, const char* format, ...) _format(3, 4);