The MoonBit Update——0122

jodie · January 22, 2024, 10:30am

MoonBit Update:

Added syntactic sugar for matrix functions to easily define local functions and anonymous functions with pattern matching:

fn init {
  fn boolean_or { // local function with pattern matching
    true, _ => true
    _, true => true
    _, _    => false
  }
  fn apply(f, x) {
    f(x)
  }
  let _ = apply(fn { x => x + 1 }, 42) // anonymous function
  let _ = apply(fn {                   // anonymous function with pattern match
    0 => 0
    1 => 1
    _ => 2
  }, 42)
}

Added syntax for constructing records using T::{ ... }. This syntax allows explicit record disambiguation and better completion for labels in the record:

struct T {
  x: Int
  y: Int
}

struct T2 {
  x: Int
  y: Int
}

fn init {
  let x = T::{x: 1, y: 2}
  debug(x.x + x.y) // 3
}

Officially removed the syntax var id = expr.
The new testing syntax test "name" {} is used to replace the original fn test_name(){}. Currently, only tests with top-level indentation are recognized as keywords, and in the future, test will no longer be supported as an identifier. Old syntax: fn test_name {} New syntax: test "name" {}
Supported the use of return statements within init or test code blocks.

fn init  {
  if i > 0 { 
    return
  }
  ...
}

test {
  if i > 0 {
    return
  }
  ...
}

Plugin Update

Improved syntax highlighting:

Before:

After: