Node

The Node generator produces a CommonJS loader and .d.ts type definitions for your functions. The generated addon uses the N-API (Node-API) interface to load the C ABI symbols and expose JS-friendly functions.

Generated artifacts

• generated/node/index.js — CommonJS loader that requires ./index.node
• generated/node/types.d.ts — function signatures inferred from your IR
• generated/node/package.json

Generated code examples

Given this IDL definition:

version: "0.1.0"
modules:
  - name: contacts
    enums:
      - name: Color
        variants:
          - { name: Red, value: 0 }
          - { name: Green, value: 1 }
          - { name: Blue, value: 2 }

    structs:
      - name: Contact
        fields:
          - { name: name, type: string }
          - { name: email, type: "string?" }
          - { name: tags, type: "[string]" }

    functions:
      - name: get_contact
        params:
          - { name: id, type: i32 }
        return: "Contact?"

      - name: list_contacts
        params: []
        return: "[Contact]"

      - name: set_favorite_color
        params:
          - { name: contact_id, type: i32 }
          - { name: color, type: "Color?" }

      - name: get_tags
        params:
          - { name: contact_id, type: i32 }
        return: "[string]"

TypeScript interfaces

Structs map to TypeScript interfaces with typed fields:

export interface Contact {
  name: string;
  email: string | null;
  tags: string[];
}

Enums

Enums map to TypeScript enums with explicit integer values:

export enum Color {
  Red = 0,
  Green = 1,
  Blue = 2,
}

Nullable types

Optional types are expressed as union types with null:

// Optional parameter
color: Color | null

// Optional return
export function get_contact(id: number): Contact | null

Array types

List types map to TypeScript arrays. Lists of optionals use parenthesized union types:

// Simple array
export function get_tags(contact_id: number): string[]

// Array return of structs
export function list_contacts(): Contact[]

// Array of optionals (if defined)
(number | null)[]

Complete generated types.d.ts

For the IDL above, the full generated file looks like:

// Generated types for WeaveFFI functions
export interface Contact {
  name: string;
  email: string | null;
  tags: string[];
}
export enum Color {
  Red = 0,
  Green = 1,
  Blue = 2,
}
// module contacts
export function get_contact(id: number): Contact | null
export function list_contacts(): Contact[]
export function set_favorite_color(contact_id: number, color: Color | null): void
export function get_tags(contact_id: number): string[]

Type mapping reference

Running the example

macOS

cargo build -p calculator
cp target/debug/libindex.dylib generated/node/index.node

cd examples/node
DYLD_LIBRARY_PATH=../../target/debug npm start

Linux

cargo build -p calculator
cp target/debug/libindex.so generated/node/index.node

cd examples/node
LD_LIBRARY_PATH=../../target/debug npm start

Notes

• The loader expects the compiled N-API addon next to it as index.node.
• The N-API addon crate is in samples/node-addon.