pawaclawczyk / scalp

example/simple_pattern_matching.php

<?php

declare(strict_types=1);

require_once __DIR__.'/../vendor/autoload.php';

use function Scalp\Conversion\AnyToString;
use function Scalp\PatternMatching\match;
use function Scalp\PatternMatching\Any;

The type Scalp\PatternMatching\Any was not found. Maybe you did not declare it correctly or list all dependencies?

use function Scalp\PatternMatching\Value;

The type Scalp\PatternMatching\Value was not found. Maybe you did not declare it correctly or list all dependencies?

use function Scalp\PatternMatching\Type;

The type Scalp\PatternMatching\Type was not found. Maybe you did not declare it correctly or list all dependencies?

use function Scalp\concat;

The type Scalp\concat was not found. Maybe you did not declare it correctly or list all dependencies?

use function Scalp\println;

The type Scalp\println was not found. Maybe you did not declare it correctly or list all dependencies?

use function Scalp\Some;
use function Scalp\Pair;

The type Scalp\Pair was not found. Maybe you did not declare it correctly or list all dependencies?

use Scalp\None;
use Scalp\Some;
use Scalp\Tuple;

function returnString(string $s): callable
{
    return function () use ($s): string {
        return $s;
    };
}

$res0 = match(42)
    ->case(Any(), function (): string { return 'Anything'; })
    ->done();

println($res0);

$res1 = match(Some(42))
    ->case(Any(), function (): string { return 'Anything'; })
    ->done();

println($res1);

$res2 = match(42)
    ->case(Value(13), function (): string { return 'Number 13'; })
    ->case(Value('42'), function (): string { return 'String "42"'; })
    ->case(Value(42), function (): string { return 'Number 42'; })
    ->case(Any(), function (): string { return 'Fallback'; })
    ->done();

println($res2);

$res3 = match(Some(42))
    ->case(Value(Some(13)), function (): string { return 'Some 13'; })
    ->case(Value(Some(42)), function (): string { return 'Some 42'; })
    ->case(Any(), function (): string { return 'Fallback'; })
    ->done();

println($res3);

$res4 = match(Some(42))
    ->case(Value(Some(13)), function (): string { return 'Some 13'; })
    ->case(Value(Some('42')), function (): string { return 'Some 42'; })
    ->case(Any(), function (): string { return 'Fallback'; })
    ->done();

println($res4);

$res5 = match(42)
    ->case(Type('string'), function (): string { return 'String'; })

Type('string') of type string is incompatible with the type Scalp\PatternMatching\Pattern\Pattern expected by parameter $pattern of Scalp\PatternMatching\UnresolvedMatchSubject::case().

    ->case(Type('integer'), function (): string { return 'Integer'; })

Type('integer') of type string is incompatible with the type Scalp\PatternMatching\Pattern\Pattern expected by parameter $pattern of Scalp\PatternMatching\MatchSubject::case().

    ->case(Any(), function (): string { return 'Not integer'; })
    ->done();

println($res5);

$res6 = match(Some(42))
    ->case(Type(None::class), function (): string { return 'None'; })
    ->case(Type(Some::class), function (): string { return 'Some'; })
    ->case(Any(), function (): string { return 'Neither'; })
    ->done();

println($res6);

$res7 = match(Some(42))
    ->case(Type(Some::class, Value('42')), returnString('Inner value is string'))

The call to type() has too many arguments starting with Value('42').

    ->case(Type(Some::class, Value(42)), returnString('Inner value is integer'))
    ->case(Any(), returnString('Fallback'))
    ->done();

println($res7);

$res8 = match(Pair('2 * 7 = ', 14))
    ->case(
        Type(Tuple::class, Any()->bind(), Any()->bind()),
        function (string $question, int $answer): string { return concat('Solution: ', $question, AnyToString($answer)); }
    )
    ->case(Any(), returnString('Fallback'))
    ->done();

println($res8);