assemblyscript/lib/demangle

demangle

Demangles AssemblyScript module exports to a friendly object structure compatible with WebIDL and TypeScript definitions.

Usage

var module = require("@assemblyscript/demangle")(myWasmModule.instance.exports);
// use module as defined in the .d.ts

Converting a memory offset (this value) to a class instance, i.e. where a class instance is returned by a WebAssembly function:

var thisValue = wasmFunctionReturningAClassInstance();
var myClass = MyClass.wrap(thisValue);

Converting a class instance to a memory offset (this value), i.e. where calling a WebAssembly function that expects a class instance:

var thisValue = myClass.this;
wasmFunctionExpectingAClassInstance(thisValue);

How does it work?

AssemblyScript modules expose their exported elements by their internal name, which is a JSDoc-style fully qualified name indicating layers of nesting, and this module is able to recreate the original object structure from those names.

• A . seperates a parent from a static child
• A # separates a parent from an instance child
• The get: prefix indicates a getter
• The set: prefix indicates a setter

Note that the compiler generates implicit getters and setters for instance fields for convenience. Support for instance members is achieved by generating wrappers that prepend the this value (offset of the instance in memory returned by the constructor) as the first argument when calling an instance method, getter or setter.