| 1: | <?php declare(strict_types=1); |
| 2: | |
| 3: | namespace TH\Maybe\Option; |
| 4: | |
| 5: | use TH\DocTest\Attributes\ExamplesSetup; |
| 6: | use TH\Maybe\Option; |
| 7: | use TH\Maybe\Result; |
| 8: | use TH\Maybe\Tests\Helpers\IgnoreUnusedResults; |
| 9: | |
| 10: | /** |
| 11: | * Return a `Option\Some` option containing `$value`. |
| 12: | * |
| 13: | * @template T |
| 14: | * @param T $value |
| 15: | * @return Option\Some<T> |
| 16: | */ |
| 17: | function some(mixed $value): Option\Some |
| 18: | { |
| 19: | return new Option\Some($value); |
| 20: | } |
| 21: | |
| 22: | /** |
| 23: | * Return a `Option\None` option containing no values. |
| 24: | */ |
| 25: | function none(): Option\None |
| 26: | { |
| 27: | return Option\None::instance; |
| 28: | } |
| 29: | |
| 30: | /** |
| 31: | * Transform a value into an `Option`. |
| 32: | * It will be a `Some` option containing `$value` if `$value` is different from `$noneValue` (default `null`) |
| 33: | * |
| 34: | * # Examples |
| 35: | * |
| 36: | * ``` |
| 37: | * self::assertEq(Option\fromValue("fruits"), Option\some("fruits")); |
| 38: | * self::assertEq(Option\fromValue(null), Option\none()); |
| 39: | * ``` |
| 40: | * |
| 41: | * @template U |
| 42: | * @param U $value |
| 43: | * @return Option<U> |
| 44: | */ |
| 45: | function fromValue(mixed $value, mixed $noneValue = null, bool $strict = true): Option |
| 46: | { |
| 47: | $same = $strict |
| 48: | ? ($value === $noneValue) |
| 49: | // @phpcs:ignore SlevomatCodingStandard.Operators.DisallowEqualOperators |
| 50: | : ($value == $noneValue); // @phpstan-ignore equal.notAllowed |
| 51: | |
| 52: | /** @var Option<U> */ |
| 53: | return $same |
| 54: | ? Option\none() |
| 55: | : Option\some($value); |
| 56: | } |
| 57: | |
| 58: | /** |
| 59: | * Execute a callable and transform the result into an `Option`. |
| 60: | * It will be a `Some` option containing the result if it is different from `$noneValue` (default `null`). |
| 61: | * |
| 62: | * # Examples |
| 63: | * |
| 64: | * Successful execution: |
| 65: | * |
| 66: | * ``` |
| 67: | * self::assertEq(Option\of(fn() => "fruits"), Option\some("fruits")); |
| 68: | * ``` |
| 69: | * |
| 70: | * Convertion of `null` to `Option\None`: |
| 71: | * |
| 72: | * ``` |
| 73: | * self::assertEq(Option\of(fn() => null), Option\none()); |
| 74: | * ``` |
| 75: | * |
| 76: | * @template U |
| 77: | * @param callable():U $callback |
| 78: | * @return Option<U> |
| 79: | */ |
| 80: | function of(callable $callback, mixed $noneValue = null, bool $strict = true): Option |
| 81: | { |
| 82: | return Option\fromValue($callback(), $noneValue, $strict); |
| 83: | } |
| 84: | |
| 85: | /** |
| 86: | * Execute a callable and transform the result into an `Option` as `Option\of()` does |
| 87: | * but also return `Option\None` if it an exception matching $exceptionClass was thrown. |
| 88: | * |
| 89: | * # Examples |
| 90: | * |
| 91: | * Successful execution: |
| 92: | * |
| 93: | * ``` |
| 94: | * self::assertEq(Option\tryOf(fn () => strtolower("FRUITS")), Option\some("fruits")); |
| 95: | * ``` |
| 96: | * |
| 97: | * Convertion of `null` to `Option\None`: |
| 98: | * |
| 99: | * ``` |
| 100: | * self::assertEq(Option\tryOf(fn() => null), Option\none()); |
| 101: | * ``` |
| 102: | * |
| 103: | * Checked Exception: |
| 104: | * |
| 105: | * ``` |
| 106: | * self::assertEq(Option\tryOf(fn () => new \DateTimeImmutable("nope")), Option\none()); |
| 107: | * ``` |
| 108: | * |
| 109: | * Unchecked Exception: |
| 110: | * |
| 111: | * ``` |
| 112: | * self::assertEq(Option\tryOf(fn () => 1 / 0), Option\none()); |
| 113: | * // @throws DivisionByZeroError Division by zero |
| 114: | * ``` |
| 115: | * |
| 116: | * @template U |
| 117: | * @template E of \Throwable |
| 118: | * @param callable():U $callback |
| 119: | * @param class-string<E> $exceptionClass |
| 120: | * @return Option<U> |
| 121: | * @throws \Throwable |
| 122: | */ |
| 123: | function tryOf( |
| 124: | callable $callback, |
| 125: | mixed $noneValue = null, |
| 126: | bool $strict = true, |
| 127: | string $exceptionClass = \Exception::class, |
| 128: | ): Option { |
| 129: | try { |
| 130: | return Option\of($callback, $noneValue, $strict); |
| 131: | } catch (\Throwable $th) { |
| 132: | if (\is_a($th, $exceptionClass)) { |
| 133: | return Option\none(); |
| 134: | } |
| 135: | |
| 136: | throw $th; |
| 137: | } |
| 138: | } |
| 139: | |
| 140: | /** |
| 141: | * Converts from `Option<Option<T>>` to `Option<T>`. |
| 142: | * |
| 143: | * # Examples |
| 144: | * |
| 145: | * ``` |
| 146: | * $x = Option\Some("vegetables"); |
| 147: | * self::assertSame(Option\flatten(Option\some($x)), $x); |
| 148: | * self::assertSame(Option\flatten(Option\some(Option\none())), Option\none()); |
| 149: | * self::assertSame(Option\flatten(Option\none()), Option\none()); |
| 150: | * ``` |
| 151: | * |
| 152: | * @template U |
| 153: | * @param Option<Option<U>> $option |
| 154: | * @return Option<U> |
| 155: | */ |
| 156: | function flatten(Option $option): Option |
| 157: | { |
| 158: | return $option instanceof Option\None |
| 159: | ? $option |
| 160: | /** @phpstan-ignore missingType.checkedException */ |
| 161: | : $option->unwrap(); |
| 162: | } |
| 163: | |
| 164: | /** |
| 165: | * Unzips an option containing a tuple of two options. |
| 166: | * |
| 167: | * If `self` is `Some([a, b])` this method returns `[Some(a), Some(b)]`. Otherwise, `[None, None]` is returned. |
| 168: | * |
| 169: | * ``` |
| 170: | * $x = Option\Some("vegetables"); |
| 171: | * self::assertEq(Option\unzip(Option\some(["a", 2])), [Option\some("a"), Option\some(2)]); |
| 172: | * self::assertSame(Option\unzip(Option\none()), [Option\none(), Option\none()]); |
| 173: | * ``` |
| 174: | * |
| 175: | * @template U |
| 176: | * @template V |
| 177: | * @param Option<array{U, V}> $option |
| 178: | * @return array{Option<U>, Option<V>} |
| 179: | */ |
| 180: | function unzip(Option $option): array |
| 181: | { |
| 182: | /** @var array{Option<U>, Option<V>} */ |
| 183: | return $option->mapOrElse( |
| 184: | static fn (array $a): array => [Option\some($a[0]), Option\some($a[1])], |
| 185: | static fn (): array => [Option\none(), Option\none()], |
| 186: | ); |
| 187: | } |
| 188: | |
| 189: | /** |
| 190: | * Transposes an `Option` of a `Result` into a `Result` of an `Option`. |
| 191: | * |
| 192: | * `None` will be mapped to `Ok(None)`. |
| 193: | * `Some(Ok(_))` and `Some(Err(_))` will be mapped to `Ok(Some(_))` and `Err(_)`. |
| 194: | * |
| 195: | * ``` |
| 196: | * use TH\Maybe\Result; |
| 197: | * |
| 198: | * self::assertEq(Result\ok(Option\some(4)), Option\transpose(Option\some(Result\ok(4)))); |
| 199: | * self::assertEq(Result\err("meat"), Option\transpose(Option\some(Result\err("meat")))); |
| 200: | * self::assertEq(Option\transpose(Option\none()), Result\ok(Option\none())); |
| 201: | * ``` |
| 202: | * |
| 203: | * @template U |
| 204: | * @template E |
| 205: | * @param Option<Result<U, E>> $option |
| 206: | * @return Result<Option<U>, E> |
| 207: | */ |
| 208: | #[ExamplesSetup(IgnoreUnusedResults::class)] |
| 209: | function transpose(Option $option): Result |
| 210: | { |
| 211: | /** @var Result<Option<U>, E> */ |
| 212: | return $option->mapOrElse( // @phpstan-ignore varTag.type |
| 213: | // @phpstan-ignore-next-line |
| 214: | static fn (Result $result) => $result->map(Option\some(...)), |
| 215: | static fn () => Result\ok(Option\none()), |
| 216: | ); |
| 217: | } |
| 218: |