PHPSA\Variable::isNumeric PHP Method

    public function isNumeric()
    {
        return $this->type & CompiledExpression::INTEGER || $this->type & CompiledExpression::DOUBLE || $this->type == CompiledExpression::NUMBER;
    }

 public function testIsNumericMethodFalseOnBoolean()
 {
     $variable = new Variable('a', 1, CompiledExpression::BOOLEAN);
     static::assertFalse($variable->isNumeric());
 }