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import { assertEquals } from "https://deno.land/std@0.79.0/testing/asserts.ts";import IO from "./IO.js";
Deno.test(  "IO: #ap - Composition",  () => {    const containerA = IO(_ => 42);    const containerB = IO(_ => x => x + 2);    const containerC = IO(_ => x => x * 2);
    assertEquals(      containerA.ap(containerB.ap(containerC.map(a => b => c => a(b(c))))).run(),      containerA.ap(containerB).ap(containerC).run()    );  });
Deno.test(  "IO: #chain - Associativity",  async () => {    const container = IO(_ => 42);    const f = x => IO(_ => x + 2);    const g = x => IO(_ => x * 2);
    assertEquals(      container.chain(f).chain(g).run(),      container.chain(value => f(value).chain(g)).run()    );  });
Deno.test(  "IO: #map - Identity",  () => {    const container = IO(_ => 42);
    assertEquals(      container.map(x => x).run(),      container.run()    );  });
Deno.test(  "IO: #map - Composition",  () => {    const container = IO(_ => 42);    const f = x => x + 2;    const g = x => x * 2;
    assertEquals(      container.map(f).map(g).run(),      container.map(x => g(f(x))).run()    );  });
Deno.test(  "IO: #of - Identity (Applicative)",  () => {    const container = IO(_ => 42);
    assertEquals(      container.ap(IO.of(x => x)).run(),      container.run()    );  });
Deno.test(  "IO: #of - Left identity (Chainable)",  async () => {    const container = IO(_ => 42);    const f = x => IO(_ => x + 2);
    assertEquals(      container.chain(IO.of).chain(f).run(),      container.chain(f).run()    );  });
Deno.test(  "IO: #of - Right identity (Chainable)",  async () => {    const container = IO(_ => 42);    const f = x => IO(_ => x + 2);
    assertEquals(      container.chain(f).chain(IO.of).run(),      container.chain(f).run()    );  });
Deno.test(  "IO: #of - Homomorphism",  () =>    assertEquals(      IO.of(42).ap(IO.of(x => x + 2)).run(),      IO.of((x => x + 2)(42)).run()    ));
Deno.test(  "IO: #of - Interchange",  () =>    assertEquals(      IO.of(42)        .ap(IO(_ => x => x + 2)).run(),      IO(_ => x => x + 2)        .ap(IO(_ => f => f(42))).run()    ));