src/NodeCompiler/CompileNodeToValue.php
private function compileConstFetch(Node\Expr\ConstFetch $constNode, CompilerContext $context)
    {
        $firstName = reset($constNode->name->parts);
        switch ($firstName) {
            case 'null':
                return null;
            case 'false':
                return false;
            case 'true':
                return true;
            default:
                if (! defined($firstName)) {
                    throw Exception\UnableToCompileNode::becauseOfNotFoundConstantReference($context, $constNode);
                }

                return constant($firstName);
        }
    }
private function compileConstFetch(Node\Expr\ConstFetch $constNode, CompilerContext $context)
    {
        $firstName = reset($constNode->name->parts);
        switch ($firstName) {
            case 'null':
                return null;
            case 'false':
                return false;
            case 'true':
                return true;
            default:
                if (! defined($firstName)) {
                    throw Exception\UnableToCompileNode::becauseOfNotFoundConstantReference($context, $constNode);
                }

                return constant($firstName);
        }
    }
Compile constant expressions

@return bool|mixed|null

@throws Exception\UnableToCompileNode