Arbitrary Module Namespace Identifiers

Allow the ability to create modules which integrate using non-IdentifierName bindings.

Rendered Spec Text

Problem

Other languages can produce values that do not match the potential strings that match IdentifierName. E.G. due to name mangling.

WebAssembly can already create such bindings since they only constrain bindings to be valid utf8 strings.

Non-identifier names can already be imported from ModuleNamespaceObjects since Abstract Module Records have no constraints on their exported names.

import * as odd from 'wasm';
odd['@foo']

Non-identifier names can be exported using export * from similarly.

export * from 'wasm'; // will export "@foo"

However, non-identifier names cannot be imported by name, exported by name, nor exported from by name. This proposal seeks to allow integration such that support to create bindings with non-identifier names can be used in those locations.

Syntax

Alteration of ExportSpecifier and ImportSpecifier are the only changes proposed:

import {"@foo" as foo} from "wasm";
export {foo as "@foo"};
export {"@bar" as bar} from "wasm";

Concerns

WebAssembly has a constraint that names must be valid UTF-8. In order to not break integration literals for the syntax must ensure they produce valid UTF-8. This means an early error must be performed so that any literal in these locations which disallows unpaired surrogates.