constant_pool

A rust macro for making constant pools much like Java enums

Usage

To define a constant pool, you must first define a struct or tuple struct type.

If you are defining a struct type, it must have a field of type &str called name. If it is a tuple struct, the first value must be of type &str.

Examples:

struct Color(&'static str, u8, u8, u8);

struct Team {
  name: &'static str,
  number: u8
}

Once your struct is defined, you can define the constant pool using the constant_pool! macro:

constant_pool! {
  pub Colors: Color {
    RED(255, 0, 0),
    BLUE(0, 0, 255),
    GREEN(0, 255, 0),
    YELLOW(0, 255, 255)
  }
}

constant_pool! {
  pub Teams: Team {
    WHITE{number: 1},
    BLACK{number: 2},
    ORANGE{number: 3}
  }
}

The name of the constant pool is defined, followed by the struct type it will use. Once defined, it creates a namespace with a module for the constant pool, populating it with all the constants you defined. For the above examples, you could access Color::RED and Team::WHITE respectively.

Additionally, the constant pool generates a slice containing all of the constant values, under Namespace::values. For our examples, this will be Color::values and Team::values. It will also generate a function to get any of the values by name, returning an Option<&T>:

let color: &Color = Color::by_name("RED").unwrap();
let team = Team::by_name("ORANGE").unwrap();