rust-typed

lib.rs:

typed

Type annotation to help rustc. This is useful for code generation.

Usage

This does not work without ufcs, because it's ambiguous.

trait ChangeWatcher<T> {
  fn is_changed(&self) -> bool;
}

struct DbConfig;
struct AppConfig;

struct Context;

impl ChangeWatcher<DbConfig> for Context {
  fn is_changed(&self) -> bool { false }
}
impl ChangeWatcher<AppConfig> for Context {
  fn is_changed(&self) -> bool { false }
}



fn some<C: ChangeWatcher<DbConfig> + ChangeWatcher<AppConfig>>(c: C) {
  if <C as ChangeWatcher<DbConfig>>::is_changed(&c) {

  }
}

But this works.

extern crate typed;
use typed::{Type, type_of};


trait ChangeWatcher<T> {
  fn is_changed(&self, _: Type<T>) -> bool;
}

struct DbConfig;
struct AppConfig;

struct Context;

impl ChangeWatcher<DbConfig> for Context {
  fn is_changed(&self, _: Type<DbConfig>) -> bool { false }
}
impl ChangeWatcher<AppConfig> for Context {
  fn is_changed(&self, _: Type<AppConfig>) -> bool { false }
}


fn some<C: ChangeWatcher<DbConfig> + ChangeWatcher<AppConfig>>(c: C) {
  if c.is_changed(type_of::<DbConfig>()) {

  }
}