add derive Register macro

src/backend/mod.rs

@@ -9,28 +9,18 @@ use std::process::Command;
 
 use anyhow::{Context, Result};
 
-use crate::register_backends;
 use crate::{Group, Package};
+use pacdef_macro::Register;
 
 pub(crate) use todo_per_backend::ToDoPerBackend;
 
 pub(in crate::backend) type Switches = &'static [&'static str];
 pub(in crate::backend) type Text = &'static str;
 
-register_backends!(Pacman, Rust);
-
-// TODO find a way to include this in the `register_backends!` macro
-pub(crate) use pacman::Pacman;
-pub(crate) use rust::Rust;
-
-// TODO find a way to include this in the `register_backends!` macro
-impl Backends {
-    fn next(&self) -> Option<Self> {
-        match self {
-            Self::Pacman => Some(Self::Rust),
-            Self::Rust => None,
-        }
-    }
+#[derive(Debug, Register)]
+pub(crate) enum Backends {
+    Pacman,
+    Rust,
 }
 
 #[derive(Debug)]