MScript

This passion project is a fully-fledged programming language that supports much of what developers seek in a language.

Classes

class Person {
  first_name: str
  last_name: str
  age: int

  constructor(self, first_name: str, last_name: str, age: int) {
    self.first_name = first_name
    self.last_name = last_name
    self.age = age
  }

  fn grow_up(self) {
    self.age += 1
  }

  fn get_full_name(self) -> str {
    return self.first_name + " " + self.last_name
  }
}

Language Interoperability

my_static_variable: int = symbol "TEST" : "/my/rust_library.so"

some_c_function: fn(int, int) -> int = symbol "add_numbers" : "/mathlib.so"

Closures

counter = fn() -> [fn() -> int, fn(), fn()] {
  state = 0
  return [
    fn() -> int {
      return state
    },
    fn() {
      modify state = state + 1
    },
    fn() {
      modify state = state - 1
    }
  ]
}

[poll_count, inc, dec] = counter()

assert poll_count() == 0
inc()
assert poll_count() == 1
dec()
dec()
assert poll_count() == -1

Strong Typing

who_is_cool = fn() -> [str...] {
  return ["Mateo", "Scout", "Tico"]
}

people: [int...] = who_is_cool() # ❌
people: [str...] = who_is_cool() # ✔️

me: bool = people[0] # ❌
me: str = people[0] # ✔️

from 1 to false step "A", bad {
  # ❌
}

from 1 to 100, number {
  print number # ✔️
}

How To Use

MScript has a build suite, mscript.exe, that can:

run MScript code
compile MScript code to bytecode
execute Precompiled MScript bytecode
transpile Human-readable bytecode to executable bytecode

Errors

This programming language is in beta production. This means that some features might break during compilation or at runtime.

If you encounter a bug in any stage of the MScript build process, please report it under the Issues tab in this repo!

An error could take the form of an explicit panic!(), which means MScript is acting in a bugged state that could not have been expected.

More commonly, an error will spawn from a bytecode instruction that cannot execute properly. The output of said occurence might look like:

******* MSCRIPT INTERPRETER FATAL RUNTIME ERROR *******
Stack Machine: [Int(5), HeapPrimitive(&"Hello")]

Call stack trace:
>> path/to/file.mmm#__fn0
 ^ path/to/another_file.mmm#Object_37::$constructor
 ^ __module__

Caused By:
  0. Reason #1
  1. Reason #2
  2. ...

Please report this at https://github.com/mrodz/mscript-lang/issues/new

My Goal

Solve a Hard Leetcode problem in my programming language! 😊