Const-trig

⚠️ Word of Warning ⚠️

WARNING, this is an extremely sketchy, half assed fork of const-trig proving const functions for f32's only, fixing errors but also introducing a new slew of bugs thanks to the instability of #![feature(const_fn_floating_point_arithmetic)].

Please proceed with caution and stay vigilant of strange behavior!

Introduction

This crate exists to provide const versions of functions, such as cos, sin, etc.

Note that this crate requires nightly Rust to unify behaviour of functions.

Crate is no longer needed when all this function will be const in std.

Any function, such as cos, sin from std can be accessed as const_trig::cos.

There aren't all trig functions, but if you want to add them, you can open a GitHub issue (someday I will read it) :) Usage:

use const_trig::{ToDegrees, ToRadians};

macro_rules! cmp {
   ($fn:ident, $e:expr) => {
       println!(concat!("const_trig::", stringify!($fn), " = {}"), const_trig::$fn($e, None));
       println!(concat!("std ", stringify!($fn), " = {}\n"), $e.$fn());
   };

   ($fn:ident, $lib:expr, $std:expr) => {
       println!(concat!("const_trig::", stringify!($fn), " = {}"), const_trig::$fn($lib, None));
       println!(concat!("std ", stringify!($fn), " = {}\n"), $std.$fn());
   };

   (! $fn:ident, $e:expr, $fnstd:ident) => {
       println!(concat!("const_trig::", stringify!($fn), " = {}"), const_trig::$fn($e, None));
       println!(concat!("std ", stringify!($fnstd), " = {}\n"), $e.$fnstd());
   };
}

fn main() {
   let sixty_degrees = 60.0f32.degrees().radians().get();
   cmp!(sin, sixty_degrees.radians(), sixty_degrees);
   cmp!(cos, sixty_degrees.radians(), sixty_degrees);

   cmp!(sqrt, 4.0f64);
   cmp!(sqrt, 2.0f64);

   cmp!(ln, 10.0f64);
   cmp!(ln, core::f64::consts::E);

   cmp!(! lg, core::f64::consts::E, log10);

   cmp!(! lb, 10.0f64, log2);

   println!("const_trig::log = {}", const_trig::log(3.5, 10.0f64, None));
   println!("std log = {}", 3.5f64.log(10.0));

   println!("{}", const_trig::root(34.0, 5, None))
}