finished default parser

src/Domain/Atoms/UnsignedIntegerAtom.php

@@ -0,0 +1,12 @@
+<?php
+namespace XaiCorp\AbcParser\Domain\Atoms;
+
+use Enzyme\Axiom\Atoms\IntegerAtom;
+
+class UnsignedIntegerAtom extends IntegerAtom
+{
+    protected function isInvalidOrFloat($value)
+    {
+        return parent::isInvalidOrFloat($value) || $value <= 0;
+    }
+}