| 1: | <?php declare(strict_types=1); |
| 2: | |
| 3: | namespace TH\Maybe\Result; |
| 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 `Result\Ok` Result containing `$value`. |
| 12: | * |
| 13: | * ``` |
| 14: | * $x = Result\ok(3); |
| 15: | * self::assertTrue($x->isOk()); |
| 16: | * self::assertSame(3, $x->unwrap()); |
| 17: | * ``` |
| 18: | * |
| 19: | * @template U |
| 20: | * @param U $value |
| 21: | * @return Result\Ok<U> |
| 22: | */ |
| 23: | function ok(mixed $value): Result\Ok |
| 24: | { |
| 25: | return new Result\Ok($value); |
| 26: | } |
| 27: | |
| 28: | /** |
| 29: | * Return a `Result\Err` result. |
| 30: | * |
| 31: | * # Examples |
| 32: | * |
| 33: | * ``` |
| 34: | * $x = Result\err("nope"); |
| 35: | * self::assertTrue($x->isErr()); |
| 36: | * self::assertSame("nope", $x->unwrapErr()); |
| 37: | * $x->unwrap(); // @throws RuntimeException Unwrapping `Err`: s:4:"nope"; |
| 38: | * ``` |
| 39: | * |
| 40: | * @template F |
| 41: | * @param F $value |
| 42: | * @return Result\Err<F> |
| 43: | */ |
| 44: | function err(mixed $value): Result\Err |
| 45: | { |
| 46: | return new Result\Err($value); |
| 47: | } |
| 48: | |
| 49: | /** |
| 50: | * Execute a callable and transform the result into an `Result`. |
| 51: | * It will be a `Result\Ok` containing the result or, if it threw an exception |
| 52: | * matching $exceptionClass, a `Result\Err` containing the exception. |
| 53: | * |
| 54: | * # Examples |
| 55: | * |
| 56: | * Successful execution: |
| 57: | * |
| 58: | * ``` |
| 59: | * self::assertEq(Result\ok(3), Result\trap(fn () => 3)); |
| 60: | * ``` |
| 61: | * |
| 62: | * Checked exception: |
| 63: | * |
| 64: | * ``` |
| 65: | * $x = Result\trap(fn () => new \DateTimeImmutable("2020-30-30 UTC")); |
| 66: | * self::assertTrue($x->isErr()); |
| 67: | * $x->unwrap(); |
| 68: | * // @throws Exception Failed to parse time string (2020-30-30 UTC) at position 6 (0): Unexpected character |
| 69: | * ``` |
| 70: | * |
| 71: | * Unchecked exception: |
| 72: | * |
| 73: | * ``` |
| 74: | * Result\trap(fn () => 1/0); |
| 75: | * // @throws DivisionByZeroError Division by zero |
| 76: | * ``` |
| 77: | * |
| 78: | * @template U |
| 79: | * @template E of \Throwable |
| 80: | * @param callable(mixed...):U $callback |
| 81: | * @param class-string<E> $exceptionClass |
| 82: | * @return Result<U,E> |
| 83: | * @throws \Throwable |
| 84: | */ |
| 85: | #[ExamplesSetup(IgnoreUnusedResults::class)] |
| 86: | function trap(callable $callback, string $exceptionClass = \Exception::class): Result |
| 87: | { |
| 88: | try { |
| 89: | /** @var Result<U,E> */ |
| 90: | return Result\ok($callback()); |
| 91: | } catch (\Throwable $th) { |
| 92: | if (\is_a($th, $exceptionClass)) { |
| 93: | return Result\err($th); |
| 94: | } |
| 95: | |
| 96: | throw $th; |
| 97: | } |
| 98: | } |
| 99: | |
| 100: | /** |
| 101: | * Converts from `Result<Result<T, E>, E>` to `Result<T, E>`. |
| 102: | * |
| 103: | * # Examples |
| 104: | * |
| 105: | * ``` |
| 106: | * $x = Result\ok(3); |
| 107: | * self::assertSame(Result\flatten(Result\ok($x)), $x); |
| 108: | * |
| 109: | * $x = Result\err("deity"); |
| 110: | * self::assertSame(Result\flatten($y = Result\ok($x)), $x); |
| 111: | * |
| 112: | * self::assertEq(Result\flatten($x), Result\err("deity")); |
| 113: | * ``` |
| 114: | * |
| 115: | * @template T |
| 116: | * @template E |
| 117: | * @template E1 of E |
| 118: | * @template E2 of E |
| 119: | * @param Result<Result<T, E1>, E2> $result |
| 120: | * @return Result<T, E> |
| 121: | */ |
| 122: | #[ExamplesSetup(IgnoreUnusedResults::class)] |
| 123: | function flatten(Result $result): Result |
| 124: | { |
| 125: | /** @phpstan-ignore return.type */ |
| 126: | return $result->mapOrElse( |
| 127: | static fn (Result $r) => $r, |
| 128: | static fn (mixed $err) => Result\err($err), |
| 129: | ); |
| 130: | } |
| 131: | |
| 132: | /** |
| 133: | * Transposes a `Result` of an `Option` into an `Option` of a `Result`. |
| 134: | * |
| 135: | * `Ok(None)` will be mapped to `None`. |
| 136: | * `Ok(Some(_))` and `Err(_)` will be mapped to `Some(Ok(_))` and `Some(Err(_))`. |
| 137: | * |
| 138: | * ``` |
| 139: | * use TH\Maybe\Option; |
| 140: | * |
| 141: | * self::assertSame(Result\transpose(Result\ok(Option\none())), Option\none()); |
| 142: | * |
| 143: | * $x = Result\ok(Option\some(4)); |
| 144: | * self::assertEq(Result\transpose($x), Option\some(Result\ok(4))); |
| 145: | * |
| 146: | * $x = Result\err("meat"); |
| 147: | * self::assertEq(Result\transpose($x), Option\some($x)); |
| 148: | * ``` |
| 149: | * |
| 150: | * @template U |
| 151: | * @template F |
| 152: | * @param Result<Option<U>, F> $result |
| 153: | * @return Option<Result<U, F>> |
| 154: | */ |
| 155: | #[ExamplesSetup(IgnoreUnusedResults::class)] |
| 156: | function transpose(Result $result): Option |
| 157: | { |
| 158: | /** @var Option<Result<U, F>> */ |
| 159: | return $result->mapOrElse( // @phpstan-ignore varTag.type |
| 160: | // @phpstan-ignore-next-line |
| 161: | static fn (Option $option) => $option->map(Result\ok(...)), |
| 162: | static fn () => Option\some(clone $result), |
| 163: | ); |
| 164: | } |
| 165: |