7import { curry } from './util.mjs';
8import { logger } from './logger.mjs';

10export function unionWithObj(a, b, func) {
11  if (b?.value !== undefined && Object.keys(b).length === 1) {
12    // https://codeberg.org/uzu/strudel/issues/1026
13    logger(`[warn]: Can't do arithmetic on control pattern.`);
14    return a;
15  }
16  const common = Object.keys(a).filter((k) => Object.keys(b).includes(k));
17  return Object.assign({}, a, b, Object.fromEntries(common.map((k) => [k, func(a[k], b[k])])));
18}
19
20export const mul = curry((a, b) => a * b);
21
22export const valued = (value) => {
23  if (value?.constructor?.name === 'Value') {
24    return value;
25  }
26  return Value.of(value);
27};
28
29export class Value {
30  constructor(value) {
31    this.value = value;
32  }
33  static of(x) {
34    return new Value(x);
35  }
36  get isNothing() {
37    return this.value === null || this.value === undefined;
38  }
39  map(f) {
40    if (this.isNothing) {
41      return this;
42    }
43    return Value.of(f(this.value));
44  }
45  mul(n) {
46    return this.map(mul).ap(n);
47  }
48  ap(other) {
49    return valued(other).map(this.value);
50  }
51  unionWith(other, func) {
52    const type = typeof this.value;
53    other = valued(other);
54    if (type !== typeof other.value) {
55      throw new Error('unionWith: both Values must have same type!');
56    }
57    if (Array.isArray(type) || type !== 'object') {
58      throw new Error('unionWith: expected objects');
59    }
60    return this.map((v) => unionWithObj(v, other.value, func));
61  }
62}
63
64export const map = curry((f, anyFunctor) => anyFunctor.map(f));