Struct coder for binary structures.

Creates a coder from an object schema of property-name to import("./mod.ts").Coder. Encodes fields in order and decodes them into an object of the same shape.

Values are added to the shared context during encode/decode, enabling import("./ref.ts").ref based length references.

It's the user's responsibility to provide a buffer big enough to fit the whole data.

Examples

Minimal usage

import { assertEquals } from "@std/assert";
import { struct } from "@hertzg/binstruct/struct";
import { u16le, u8le } from "@hertzg/binstruct/numeric";

const coder = struct({ id: u16le(), flag: u8le() });
const value = { id: 513, flag: 7 };
const buf = new Uint8Array(32);
const written = coder.encode(value, buf);
const [decoded, read] = coder.decode(buf);

assertEquals(decoded, value);
assertEquals(written, read);

Functions

f
struct<T extends Record<string, Coder<any>>>(schema: T): Coder<StructDecoded<T>>

Creates a Coder for structured data from an object of property names to coders.

Type Aliases

T
StructDecoded<T extends Record<string, Coder<any>>> = [K in keyof T]: T[K] extends Coder<infer U> ? U : never

The decoded object type of a struct schema: each property's coder Coder<U> contributes a property of type U.

Usage

import * as mod from "struct/struct.ts";