Writing WASM with AssemblyScript

While there are many options to actually generate valid WASM, one of the most attractive ways is to use AssemblyScript. AssemblyScript is a language that looks and feels quite similar to TypeScript, making it rather easy to learn from a syntax perspective. Under the hood, however, there are still some concepts relating to WASM that need to be known in order to write mid-sized to larger AssemblyScript applications or libraries.

One of the core concepts of AssemblyScript is to model the different data types used in WASM. For instance, using integers requires the use of the i32 type.

Let’s have a look at some example code. We’ll start with a small function that expects two parameters, adds them up, and returns the result:

module.ts

export function sum(a: i32, b: i32): i32 {
  return a + b;
}

With the exception of the i32 type, everything in the preceding example looks and feels just like TypeScript. Even the file...