const-ft

A macro for easy generation and wrapping of a const function under a const_fn feature gate.

Installation:

toml const_ft = { version = "0.1" }

You can enable the feature by having a feature in the project enable the feature from the crate:

toml [features] const = ["const_ft/const_fn"]

Usage:

rust const_ft! { pub fn some_function() -> usize { 1usize }

Requirement:

By using the macro, your code changes from ```rust

![cfgattr(feature = "constfn", feature(const_fn))]

 #[cfg(feature = "const_fn")]
 pub const fn some_function() -> usize {
     1usize
 }

 #[cfg(not(feature = "const_fn"))]
 pub fn some_function() -> usize {
    1usize
 }

```

to

```rust

![cfgattr(feature = "constfn", feature(const_fn))]

#[macrouse] extern crate constft;

constft! { pub fn somefunction() -> usize { 1usize } } ```