update to PHP-8.1

[m6w6/seekat] / lib / API / Future / Common.php

diff --git a/lib/API/Future/Common.php b/lib/API/Future/Common.php
new file mode 100644 (file)
index 0000000..afbc62e
--- /dev/null
+++ b/lib/API/Future/Common.php
@@ -0,0 +1,52 @@
+<?php
+
+namespace seekat\API\Future;
+
+use seekat\API\Future;
+use seekat\Exception\UnexpectedValueException;
+
+abstract class Common implements Future {
+       protected \WeakMap $cancellations;
+       protected string $promiseType;
+
+       public function __construct() {
+               if (empty($this->promiseType)) {
+                       throw new UnexpectedValueException("Promise type must be set in Future implementation");
+               }
+               $this->cancellations = new \WeakMap;
+       }
+
+       function isPromise(object $promise): bool {
+               return $promise instanceof $this->promiseType;
+       }
+
+       function getPromise(object $context) : object {
+               return $context->promise();
+       }
+
+       function cancelPromise(object $promise) : void {
+               if (isset($this->cancellations[$promise])) {
+                       $this->cancellations[$promise]();
+               }
+       }
+
+       function resolve(mixed $value) : object {
+               $context = $this->createContext();
+               $promise = $context->promise();
+               $context->resolve($value);
+               return $promise;
+       }
+
+       function resolver(object $context) : \Closure {
+               return function($value) use($context) {
+                       $context->resolve($value);
+               };
+       }
+
+       function reducer() : \Closure {
+               return function(array $promises) {
+                       return $this->all($promises);
+               };
+       }
+
+}