import {
  fixedArray,
  number,
  string,
  validate,
  type ValidationFailure,
  type Validator,
} from "https://deno.land/x/abstruct@$VERSION/mod.ts";
import type {
  Assert,
  Has,
  IsExact,
} from "https://deno.land/std/testing/types.ts";
import { assertEquals } from "https://deno.land/std/testing/asserts.ts";

const Tuple = fixedArray(string, number);

type doTest = Assert<
  Has<typeof Tuple, Validator<[unknown, unknown], [string, number]>>,
  true
>;

const result = validate(Tuple, [0, ""]);
declare const failure: ValidationFailure;

if (result.isOk()) {
  type doTest = Assert<IsExact<typeof result.value, [string, number]>, true>;
} else {
  assertEquals(result.value, [failure, failure]);
}

maxFailures

The maximum number of ValidationFailure. It should be positive integer. The default is Number.MAX_SAFE_INTEGER.

Example of fail fast:

import {
  fixedArray,
  number,
  string,
  validate,
  type ValidationFailure,
  type Validator,
} from "https://deno.land/x/abstruct@$VERSION/mod.ts";
import type {
  Assert,
  Has,
  IsExact,
} from "https://deno.land/std/testing/types.ts";
import { assertEquals } from "https://deno.land/std/testing/asserts.ts";

const Tuple = fixedArray(string, number);
const result = validate(Tuple, [0, ""], { maxFailures: 1 });
declare const failure: ValidationFailure;

if (result.isErr()) {
  assertEquals(result.value, [failure]);
}

Because the validator performs lazy evaluation, limiting the number of errors improves performance.