function refineFields
refineFields<
TCoders extends FieldCoders,
THost extends [K in keyof TCoders]: Uint8Array
>(coders: TCoders): Refiner<THost, Omit<THost, keyof TCoders> & DecodedFields<TCoders>, []>

Creates a Refiner that swaps named Uint8Array fields of a host record for the typed values produced by their sub-coders. Fields not in coders are passed through unchanged.

Pair with refine to apply the refinement to a host coder, or use as an arm of refineSwitch for layered formats where the host's discriminator picks which sub-coder to use.

Examples

Refine a payload field with a nested coder

import { assertEquals } from "@std/assert";
import { bytes, refine, refineFields, struct, u16be, u8 } from "@hertzg/binstruct";

const inner = struct({ a: u8(), b: u8() });
const outer = struct({ tag: u16be(), payload: bytes(2) });

const coder = refine(outer, refineFields({ payload: inner }))();
const buffer = new Uint8Array(4);

coder.encode({ tag: 0xbeef, payload: { a: 1, b: 2 } }, buffer);
const [decoded] = coder.decode(buffer);

assertEquals(decoded, { tag: 0xbeef, payload: { a: 1, b: 2 } });

Type Parameters

TCoders extends FieldCoders

Map of field name to sub-coder.

THost extends [K in keyof TCoders]: Uint8Array

Host record; constrained so each refined field is Uint8Array on the unrefined side.

Parameters

coders: TCoders

Map of field names to per-field sub-coders.

Return Type

A refiner from THost to THost with the listed fields replaced by their decoded values.

Usage

import { refineFields } from "refine/refine.ts";