abstruct

import {
  and,
  assert,
  maxCount,
  pattern,
  props,
  string,
  validDate,
} from "https://deno.land/x/abstruct@$VERSION/mod.ts";
import { assertThrows } from "https://deno.land/std/testing/asserts.ts";

const Id = and(string, pattern(/^\d$/));
const Book = props({
  id: Id,
  title: maxCount(256).expect(`length should be less than or equal to 256`),
  publishAt: validDate,
});

assertThrows(() =>
  assert(Book, {
    id: 0,
    title: "Harry Potter and the Philosopher's Stone",
    publishAt: new Date("1997/6/26"),
  })
);

import {
  and,
  gte,
  int,
  lte,
  validate,
} from "https://deno.land/x/abstruct@$VERSION/mod.ts";

const Int8 = and(
  int,
  gte(-127),
  lte(128),
);
declare const input: number;

const result = validate(Int8, input);

if (result.isOk()) {
  // result.value;
} else {
  // result.value;
}

import {
  and,
  assert,
  gte,
  instance,
  lte,
  validDate,
} from "https://deno.land/x/abstruct@$VERSION/mod.ts";
import { Assert, IsExact } from "https://deno.land/std/testing/types.ts";

const ValidDate = and(
  instance(Date),
  validDate,
  gte(new Date("1970/1/1")),
  lte(new Date("2038/1/19")),
);
const input: unknown = null;

assert(ValidDate, input);

type doTest = Assert<IsExact<typeof input, Date>, true>;

import { int8, string } from "https://deno.land/x/abstruct@$VERSION/mod.ts";

const Int8 = int8.expect("should be int8!!!");
const ID = string.expect(({ input }) =>
  `id should be string, actual ${typeof input}`
);