#constructor #macro-derive #macro

macro derived

Derive macros for automating the boring stuff

7 unstable releases (3 breaking)

0.4.2 Sep 29, 2021
0.4.1 Sep 29, 2021
0.3.1 Sep 27, 2021
0.2.0 Sep 25, 2021
0.0.1 Sep 25, 2021

#53 in #constructor

Apache-2.0

34KB
644 lines

derived: Macros for automating the boring stuff

GitHub Workflow Status Crates.io docs.rs GitHub

The derived crate provides macros that can simplify all the boring stuff, like writing constructors for example. With this crate, you can create compile-time, constant default implementations, constructors, getters and setters with full generics and lifetime support.

Features

  • ☑️ Ctor: To generate constructors
  • 🤌 Gtor: To generate getters
  • ⚙️ Stor: To generate setters
  • 🪄 Constdef: To generate constant, compile-time default implementations.

    🎉 Arrays, tuples, nested tuples in arrays and nested arrays in tuples included!

  • 💯 Full lifetimes, generics and where clause support
  • 🤓 Advanced features:
    • Use the gtor attribute to get either immutable or mutable or both references (see example below)
    • Skip generation of setters or getters with the #[stor_skip] or #[gtor_skip] attributes for specific fields
    • Make ctors and gtors const with the #[ctor_const] and #[gtor_const] attributes
    • Skip ctors, gtors and stors for PhantomData fields with the #[phantom] attribute

Example: Constant default implementations

use derived::Constdef;

#[derive(Constdef)]
struct MyConst {
    a: u8,
    b: bool,
    c: char,
}

const MYCONST: MyConst = MyConst::default();
// use it with other consts
const ZERO_U8: u8 = MYCONST.a;

assert_eq!(MYCONST.a, 0);
assert_eq!(MYCONST.b, false);
assert_eq!(MYCONST.c, '\0');

Example: Generating constructors

use derived::Ctor;

#[derive(Ctor)]
pub struct MyStruct {
    a: u8,
    b: i8,
}

let mystruct = MyStruct::new(1, -1);
assert_eq!(mystruct.a, 1);
assert_eq!(mystruct,b, -1);

Example: Generating getters

use derived::{Ctor, Gtor};

// we'll derive `Ctor` to avoid having to write ctors
#[derive(Ctor, Gtor)]
pub struct MyStruct {
    name: String,
    userid: u64,
}

let ms = MyStruct::new("Sayan".to_owned(), 1);
assert_eq!(ms.get_name(), "sayan");
// we don't need to deref because u64 is a copy type
assert_eq!(ms.get_userid(), 1);

Example: Generating setters

use derived::{Ctor, Stor};

// we'll derive `Ctor` to avoid having to write ctors
#[derive(Ctor, Stor)]
pub struct MyStruct {
    name: String,
    userid: u64,
}

let mut ms = MyStruct::new("Sayan".to_owned(), 1);
assert_eq!(ms.get_name(), "sayan");
// we don't need to deref because u64 is a copy type
assert_eq!(ms.get_userid(), 1);
ms.set_userid(0);
assert_eq!(ms.get_userid(), 0);

Example: Adanced generics and lifetimes in structs

use derived::{Ctor, Gtor};

#[derive(Ctor, Gtor)]
struct MyTag<'a, T: ToString> {
    val: &'a T,
    tag: u8,
}

let mut x = MyTag::new(&10i32, 20); // this will have type MyTag<i32>
// you can now use getters and setters as you please!
assert_eq!(x.get_val().to_string(), "10");
x.set_val(11);
assert_eq!(x.get_val().to_string(), "11");

Example: get_mut and get

use derived::{Ctor, Gtor};

#[derive(Ctor, Gtor)]
#[gtor(get, get_mut)]
pub struct Mutable {
    x_axis: u8,
    y_axis: u8,
}

#[test]
fn test_get_and_get_mut() {
    let mut m = Mutable::new(0, 0);
    // move x by 1 unit
    *m.get_x_axis_mut() = 1;
    // move y by 2 units
    *m.get_y_axis_mut() = 2;
    assert_eq!(m.get_x_axis(), 1);
    assert_eq!(m.get_y_axis(), 2);
}

License

This crate is distributed under the Apache-2.0 License.

Dependencies

~1.5MB
~37K SLoC