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import { assertIsEquivalent } from "./asserts.js";import Maybe from "./Maybe.js";
Deno.test(  "Maybe: #just",  () =>    assertIsEquivalent(Maybe.just(42), Maybe.Just(42)));
Deno.test(  "Maybe.Just: #alt",  () =>    assertIsEquivalent(      Maybe.Just(42).alt(Maybe.Just(24)),      Maybe.Just(42)    ));
Deno.test(  "Maybe.Just: #ap - Composition",  () => {    const containerA = Maybe.Just(42);    const containerB = Maybe.Just(x => x + 2);    const containerC = Maybe.Just(x => x * 2);
    assertIsEquivalent(      containerA.ap(containerB.ap(containerC.map(a => b => c => a(b(c))))),      containerA.ap(containerB).ap(containerC)    );  });
Deno.test(  "Maybe.Just: #ap with either",  () => {    const lift2 = (f, a, b) => b.ap(a.map(f));    const either = (x, y) => lift2(a => b => a || b, x, y);
    assertIsEquivalent(      either(        Maybe.Just(false),        Maybe.Just(82)      ),      Maybe.Just(82)    );  });
Deno.test(  "Maybe.Just: #ap with lift",  () => {    const lift2 = (f, a, b) => b.ap(a.map(f));
    const containerA = Maybe.Just(42);    const containerB = Maybe.Just(32);
    assertIsEquivalent(      lift2(x => y => x * y, containerA, containerB),      Maybe.Just(1344)    );  });
Deno.test(  "Maybe.Just: #ap with merge",  () => {    const append = y => xs => xs.concat([y]);    const lift2 = (f, a, b) => b.ap(a.map(f));    const merge = (T, xs) => xs.reduce(      (acc, x) => lift2(append, x, acc),      T.of([])    );
    assertIsEquivalent(      merge(        Maybe,        [          Maybe.Just(2),          Maybe.Just(10),          Maybe.Just(3)        ]      ),      Maybe.Just([ 2, 10, 3 ])    );  });
Deno.test(  "Maybe.Just: #filter (even)",  () =>    assertIsEquivalent(      Maybe.Just(42).filter(x => x % 2 === 0),      Maybe.Just(42)    ));
Deno.test(  "Maybe.Just: #filter (odd)",  () =>    assertIsEquivalent(      Maybe.Just(23).filter(x => x % 2 === 0),      Maybe.Nothing    ));
Deno.test(  "Maybe.Just: #map",  () =>    assertIsEquivalent(      Maybe.Just(42).map(x => x * 2),      Maybe.Just(84)    ));
Deno.test(  "Maybe.Just: #map - Identity",  () => {    const container = Maybe.Just(42);
    assertIsEquivalent(      container.map(x => x),      container    );  });
Deno.test(  "Maybe.Just: #map - Composition",  () => {    const container = Maybe.Just(42);    const f = x => x + 2;    const g = x => x * 2;
    assertIsEquivalent(      container.map(f).map(g),      container.map(x => g(f(x)))    );  });
Deno.test(  "Maybe.Nothing: #alt",  () =>    assertIsEquivalent(      Maybe.Nothing.alt(Maybe.Just(42)),      Maybe.Just(42)    ));
Deno.test(  "Maybe.Nothing: #filter",  () =>    assertIsEquivalent(      Maybe.Nothing.filter(x => x % 2 === 0),      Maybe.Nothing    ));
Deno.test(  "Maybe.Nothing: #map",  () =>    assertIsEquivalent(      Maybe.Nothing.map(x => x * 2),      Maybe.Nothing    ));
Deno.test(  "Maybe.Nothing: #map - Identity",  () => {    const container = Maybe.Nothing;
    assertIsEquivalent(      container.map(x => x),      container    );  });
Deno.test(  "Maybe.Nothing: #map - Composition",  () => {    const container = Maybe.Nothing;    const f = x => x + 2;    const g = x => x * 2;
    assertIsEquivalent(      container.map(f).map(g),      container.map(x => g(f(x)))    );  });