weekly 2024-01-08

MoonBit Update

• Now we have removed the interface keyword officially, replacing it with trait.

• Based on community feedback, we've introduced the syntax let mu t id = expr to replace var id = expr. Support for var id = expr will be removed next week.

• Added Default implementation for the Array type:

fn init {
  debug(Array::default()) // []
}

• Added Default, Eq, and Debug implementations for the List type:

fn init {
  let l1: List[_] = Cons(1, Cons(2, Cons(3, List::default())))
  let l2: List[_] = Cons(1, Cons(2, Cons(4, Nil)))
  debug(l1) // Cons(1, Cons(2, Cons(3, Nil)))
  debug(l1 == l2) // false
  debug(l2 == l2) // true
}

• Fixed type checking for public function bodies. For example:

priv type T
pub fn f() {
  let t: T = ... // public definition cannot depend on private type
      ...
}

This used to cause an error in T, it will no longer result in such an issue.

Plugin Update

• We've integrated the MoonBit AI, now available at https://ai.moonbitlang.com, feel free to try it.

• Resolved several issues to enhance the stability of the LSP, preventing unexpected crashes.

Build System Update

• Fixed an issue where moon test would test packages in the .mooncakes folder.

• Deprecated moon check --daemon.

• Improved error messages for incorrect format or content in moon.pkg.json.