chore: update codebase to PHP 8.1

docs/typeclasses/Applicative.md

@@ -17,7 +17,7 @@ interface Applicative extends Apply
      * @param A $a
      * @return F<A>
      */
-    public function pure($a);
+    public function pure(mixed $a);
 }
 ```
 
@@ -34,7 +34,7 @@ The `Applicative` typeclass needs to satisfy four laws in addition to the `Apply
 ### Identity
 
 ```php
-$applicative->apply($applicative->pure(fn($x) => $x), $y) == $y
+$applicative->apply($applicative->pure(fn(mixed $x): mixed => $x), $y) == $y
 ```
 
 ### Composition

docs/typeclasses/Bifunctor.md

@@ -63,13 +63,13 @@ variables
 ### Identity
 
 ```php
-$bifunctor->biMap(fn($x) => $x, fn($x) => $x, $a) == $a
+$bifunctor->biMap(fn(mixed $x): mixed => $x, fn(mixed $x): mixed => $x, $a) == $a
 ```
 
 ### Composition
 
 ```php
-$bifunctor->biMap(fn($x) => $f($g($x)), fn($x) => $h($k($x)), $a) == $bifunctor->biMap(fn($x) => $f($x), fn($x) => $h($x), $bifunctor->biMap(fn($x) => $g($x), fn($x) => $k($x)), $a)
+$bifunctor->biMap(fn(mixed $x): mixed => $f($g($x)), fn(mixed $x): mixed => $h($k($x)), $a) == $bifunctor->biMap(fn(mixed $x): mixed => $f($x), fn(mixed $x): mixed => $h($x), $bifunctor->biMap(fn(mixed $x): mixed => $g($x), fn(mixed $x): mixed => $k($x)), $a)
 ```
 
 ## Implemented instances

docs/typeclasses/Functor.md

@@ -39,15 +39,15 @@ A `Functor` instance needs to abide by two laws:
 The identity function should be mapped to the identity function
 
 ```php
-$functor->map(fn($x) => $x, $y) == $y
+$functor->map(fn(mixed $x): mixed => $x, $y) == $y
 ```
 
 ### Composition
 
 Mapping the composition of two functions or composing the mapping of those functions should be the same thing
 
 ```php
-$functor->map(fn($x) => $f($g($x)), $y) == $functor->map(fn($x) => $f($x), $functor->map(fn($x) => $g($x), $y))
+$functor->map(fn(mixed $x): mixed => $f($g($x)), $y) == $functor->map(fn(mixed $x): mixed => $f($x), $functor->map(fn(mixed $x): mixed => $g($x), $y))
 ```
 
 ## Implemented instances

docs/typeclasses/Monad.md

@@ -65,13 +65,13 @@ $monad->bind($monad->pure($a), $f) == $f($a)
 ### Right identity
 
 ```php
-$monad->bind($a, fn($x) => $monad->pure($x)) == $a
+$monad->bind($a, fn(mixed $x): mixed => $monad->pure($x)) == $a
 ```
 
 ### Associativity
 
 ```php
-$monad->bind($a, fn($x) => $monad->bind($f($x), $g)) == $monad->bind($monad->bind($a, $g), $g)
+$monad->bind($a, fn(mixed $x): mixed => $monad->bind($f($x), $g)) == $monad->bind($monad->bind($a, $g), $g)
 ```
 
 ## Implemented instances

docs/typeclasses/Profunctor.md

@@ -66,12 +66,12 @@ contravariant type variable.
 ### Identity
 
 ```php
-$profunctor->diMap(fn($x) => $x, fn($x) => $x, $a) == $a
+$profunctor->diMap(fn(mixed $x): mixed => $x, fn(mixed $x): mixed => $x, $a) == $a
 ```
 
 ### Composition
 
 ```php
-$profunctor->diMap(fn($x) => $f($g($x)), fn($x) => $h($k($x)), $a) == $profunctor->diMap(fn($x) => $g($x), fn($x) => $h($x), $profunctor->diMap(fn($x) => $f($x), fn($x) => $k($x)), $a)
+$profunctor->diMap(fn(mixed $x): mixed => $f($g($x)), fn(mixed $x): mixed => $h($k($x)), $a) == $profunctor->diMap(fn(mixed $x): mixed => $g($x), fn(mixed $x): mixed => $h($x), $profunctor->diMap(fn(mixed $x): mixed => $f($x), fn(mixed $x): mixed => $k($x)), $a)
 ```
 

docs/typeclasses/Traversable.md

@@ -54,7 +54,7 @@ $t($traversable->traverse($applicative, $f, $x)) == $traversable->traverse($appl
 ### Identity
 
 ```php
-$traversable->traverse(new IdentityApplicative(), fn($x) => new Identity($x), $y) == new Identity($y)
+$traversable->traverse(new IdentityApplicative(), fn(mixed $x): mixed => new Identity($x), $y) == new Identity($y)
 ```
 
 ### Composition

src/Either.php

@@ -25,7 +25,6 @@
 use Marcosh\LamPHPda\Typeclass\Functor;
 use Marcosh\LamPHPda\Typeclass\Monad;
 use Marcosh\LamPHPda\Typeclass\Traversable;
-use Throwable;
 
 /**
  * @see https://github.com/marcosh/lamphpda/tree/master/docs/data-structures/Either.md
@@ -41,25 +40,18 @@
  */
 final class Either implements DefaultMonad, DefaultTraversable, HK2Covariant
 {
-    private bool $isRight;
-
-    /** @var null|A */
-    private $leftValue;
-
-    /** @var null|B */
-    private $rightValue;
-
     /**
      * @param null|A $leftValue
      * @param null|B $rightValue
      *
      * @psalm-mutation-free
      */
-    private function __construct(bool $isRight, $leftValue = null, $rightValue = null)
+    private function __construct(
+        private readonly bool $isRight,
+        private mixed $leftValue = null,
+        private mixed $rightValue = null
+    )
     {
-        $this->isRight = $isRight;
-        $this->leftValue = $leftValue;
-        $this->rightValue = $rightValue;
     }
 
     /**
@@ -70,7 +62,7 @@ private function __construct(bool $isRight, $leftValue = null, $rightValue = nul
      *
      * @psalm-pure
      */
-    public static function left($value): self
+    public static function left(mixed $value): self
     {
         return new self(false, $value);
     }
@@ -83,7 +75,7 @@ public static function left($value): self
      *
      * @psalm-pure
      */
-    public static function right($value): self
+    public static function right(mixed $value): self
     {
         return new self(true, null, $value);
     }
@@ -147,62 +139,62 @@ public function eval(
      * @param A $a
      * @return A
      */
-    public function fromLeft($a)
+    public function fromLeft(mixed $a): mixed
     {
         return $this->eval(
             /**
              * @param A $aa
              * @return A
              */
-            static fn ($aa) => $aa,
+            static fn (mixed $aa): mixed => $aa,
             /**
              * @param B $_
              * @return A
              */
-            static fn ($_) => $a
+            static fn (mixed $_): mixed => $a
         );
     }
 
     /**
      * @param B $b
      * @return B
      */
-    public function fromRight($b)
+    public function fromRight(mixed $b): mixed
     {
         return $this->eval(
             /**
              * @param A $_
              * @return B
              */
-            static fn ($_) => $b,
+            static fn (mixed $_): mixed => $b,
             /**
              * @param B $bb
              * @return B
              */
-            static fn ($bb) => $bb
+            static fn (mixed $bb): mixed => $bb
         );
     }
 
     /**
-     * @throws Throwable
      * @return B
+     * @throws \Throwable
      */
-    public function fromRightThrow(Throwable $e)
+    public function fromRightThrow(\Throwable $e): mixed
     {
         return $this->eval(
             /**
              * @param A $_
-             * @throws Throwable
              * @return B
+             * @throws \Throwable
              */
-            static function ($_) use ($e) {
+            static function (mixed $_) use ($e): never {
                 throw $e;
             },
             /**
              * @param B $b
              * @return B
              */
-            static fn ($b) => $b
+            static fn (mixed $b): mixed => $b
         );
     }
 
@@ -213,7 +205,7 @@ public function toMaybe(): Maybe
     {
         return $this->eval(
             static fn (): Maybe => Maybe::nothing(),
-            static fn ($b): Maybe => Maybe::just($b)
+            static fn (mixed $b): Maybe => Maybe::just($b)
         );
     }
 
@@ -289,7 +281,7 @@ public function mapLeft(callable $f): self
              * @param B $b
              * @return B
              */
-            static fn ($b) => $b
+            static fn (mixed $b): mixed => $b
         );
     }
 
@@ -330,7 +322,7 @@ public function apply(HK1 $f): self
      *
      * @psalm-pure
      */
-    public static function ipure(Applicative $applicative, $a): self
+    public static function ipure(Applicative $applicative, mixed $a): self
     {
         return self::fromBrand($applicative->pure($a));
     }
@@ -345,7 +337,7 @@ public static function ipure(Applicative $applicative, $a): self
      *
      * @psalm-suppress LessSpecificImplementedReturnType
      */
-    public static function pure($a): self
+    public static function pure(mixed $a): self
     {
         return self::ipure(new EitherApplicative(), $a);
     }
@@ -387,7 +379,7 @@ public function bind(callable $f): self
      *
      * @psalm-mutation-free
      */
-    public function ifoldr(Foldable $foldable, callable $f, $b)
+    public function ifoldr(Foldable $foldable, callable $f, mixed $b): mixed
     {
         /** @psalm-suppress ArgumentTypeCoercion */
         return $foldable->foldr($f, $b, $this);
@@ -401,7 +393,7 @@ public function ifoldr(Foldable $foldable, callable $f, $b)
      *
      * @psalm-mutation-free
      */
-    public function foldr(callable $f, $b)
+    public function foldr(callable $f, mixed $b): mixed
     {
         return $this->ifoldr(new EitherFoldable(), $f, $b);
     }

src/IO.php

@@ -66,7 +66,7 @@ public static function fromBrand(HK1 $hk): self
     /**
      * @return A
      */
-    public function eval()
+    public function eval(): mixed
     {
         /** @psalm-suppress ImpureFunctionCall */
         return ($this->action)();
@@ -122,7 +122,7 @@ public function apply(HK1 $f): self
      *
      * @psalm-pure
      */
-    public static function ipure(Applicative $applicative, $a): self
+    public static function ipure(Applicative $applicative, mixed $a): self
     {
         return self::fromBrand($applicative->pure($a));
     }
@@ -134,7 +134,7 @@ public static function ipure(Applicative $applicative, $a): self
      *
      * @psalm-pure
      */
-    public static function pure($a): self
+    public static function pure(mixed $a): self
     {
         return self::ipure(new IOApplicative(), $a);
     }

src/Identity.php

@@ -34,17 +34,11 @@
  */
 final class Identity implements DefaultMonad, DefaultTraversable
 {
-    /**
-     * @var A
-     */
-    private $value;
-
     /**
      * @param A $value
      */
-    private function __construct($value)
+    private function __construct(private readonly mixed $value)
     {
-        $this->value = $value;
     }
 
     /**
@@ -54,7 +48,7 @@ private function __construct($value)
      *
      * @psalm-pure
      */
-    public static function wrap($value): self
+    public static function wrap(mixed $value): self
     {
         return new self($value);
     }
@@ -75,7 +69,7 @@ public static function fromBrand(HK1 $b): self
     /**
      * @return A
      */
-    public function unwrap()
+    public function unwrap(): mixed
     {
         return $this->value;
     }
@@ -138,7 +132,7 @@ public function apply(HK1 $f): self
      *
      * @psalm-pure
      */
-    public static function ipure(Applicative $applicative, $a): self
+    public static function ipure(Applicative $applicative, mixed $a): self
     {
         return self::fromBrand($applicative->pure($a));
     }
@@ -152,7 +146,7 @@ public static function ipure(Applicative $applicative, $a): self
      *
      * @psalm-suppress LessSpecificImplementedReturnType
      */
-    public static function pure($a): self
+    public static function pure(mixed $a): self
     {
         return self::ipure(new IdentityApplicative(), $a);
     }
@@ -191,7 +185,7 @@ public function bind(callable $f): self
      *
      * @psalm-suppress ArgumentTypeCoercion
      */
-    public function ifoldr(Foldable $foldable, callable $f, $b)
+    public function ifoldr(Foldable $foldable, callable $f, mixed $b): mixed
     {
         return $foldable->foldr($f, $b, $this);
     }
@@ -202,7 +196,7 @@ public function ifoldr(Foldable $foldable, callable $f, $b)
      * @param B $b
      * @return B
      */
-    public function foldr(callable $f, $b)
+    public function foldr(callable $f, mixed $b): mixed
     {
         return $this->ifoldr(new IdentityFoldable(), $f, $b);
     }