Fixes based on phpstan.

Author: smuuf

src/Repl.php

@@ -8,7 +8,7 @@
 use \Smuuf\Primi\Helpers\Common;
 use \Smuuf\Primi\Colors;
 use \Smuuf\Primi\Interpreter;
-use \Smuuf\Primi\Context;
+use \Smuuf\Primi\IContext;
 use \Smuuf\Primi\IReadlineDriver;
 
 class Repl extends \Smuuf\Primi\StrictObject {
@@ -123,7 +123,7 @@ private static function formatType(Value $value) {
 
 	}
 
-	private function printContext(Context $c): void {
+	private function printContext(IContext $c): void {
 
 		foreach ($c->getVariables() as $name => $value)  {
 			echo "$name: ";

src/extensions/psl/CastingExtension.php

@@ -29,7 +29,7 @@ public static function to_string(Value $value): StringValue {
 	public static function to_regex(Value $value): RegexValue {
 
 		// Allow regexes to be casted to regex.
-		if ($value instanceof Regex) {
+		if ($value instanceof RegexValue) {
 			return $value;
 		}