INITIAL COMMIT

.gitignore

+/composer.phar
+/vendor
+/.idea
+/composer.lock

composer.json

+{
+	"name": "jkuchar/assert-function",
+	"description": "Assert function/closure signature type.",
+	"minimum-stability": "stable",
+	"license": "New BSD",
+	"authors": [
+		{
+			"name": "Jan Kuchař",
+			"email": "honza.kuchar@grifart.cz"
+		}
+	],
+
+	"require-dev": {
+		"nette/tester": "~1.7.1"
+	},
+
+	"autoload": {
+		"psr-4": {
+			"Grifart\\AssertFunction\\": "src"
+		},
+		"files": [
+			"src/functions.php"
+		]
+	},
+
+	"autoload-dev": {
+		"psr-4": {
+			"Grifart\\AssertFunction\\": "tests"
+		}
+	}
+
+}

src/functions.php

+<?php declare(strict_types=1);
+/**
+ * Used to load functions.
+ */
+
+namespace Grifart\AssertFunction;
+
+function parameters(string ...$params): array
+{
+	return $params;
+}
+
+function optional(string $classType): string
+{
+	return '?' . $classType;
+}
+
+function assertFunction(callable $fn, array $parameters, string $returnType): void
+{
+
+}

tests/bootstrap.php

+<?php declare(strict_types=1);
+require __DIR__ . '/../vendor/autoload.php';
+
+\Tester\Environment::setup();
+

tests/optional.phpt

+<?php declare(strict_types=1);
+namespace MyTestNamespace;
+require __DIR__ . '/bootstrap.php';
+
+use function Grifart\AssertFunction\optional;
+use Tester\Assert;
+
+class TestClass {};
+
+Assert::equal('?MyTestNamespace\TestClass', optional(TestClass::class));