Version 3

[stephenwf]

Some improvements that I'd like to make:

• Fix union types
• Remove generic building of main types
• Ensure supported services are valid
• Add generic types to create Normalized variants programatically
• Add more type tests
• Add cast() function to package, 3 sigs:
  • cast({ type: 'Manifest' }) -> Manifest
  • cast<'Manifest'>({}) -> Manifest
  • cast({}, 'Manifest') -> Manifest

Cast function

At the moment this package isn't a fully-typescript only package - it does have an empty JS file. For non-typescript projects in an IDE like VSCode this can still be useful if the types are available. The cast function will be an essentially empty (a) => a function with types.

Casting fixed values.
Use case: test fixtures.

const manifest = {
  id: '...',
  type: 'Manifest',
  // ...
};

const typedManifest = cast(manifest); // Typed inferred from `manifest.type` value

Casting based on known type

const manifest = await fetchManifest(); // { id: ... }

const typedManifest = cast(manifest, 'Manifest'); // Type inferred from second argument

Casting with generic (TS ONLY)

const manifest = await fetchManifest();

const typedManifest = cast<'Manifest'>(manifest); // Type from generic argument and can be dynamic.