src/Values/Size.php
public function add(self $other): self
    {
        return self::from($this->value + $other->value);
    }
public function add(self $other): self
    {
        return self::from($this->value + $other->value);
    }
public function add ( self $ other ) : self { return self :: from ( $ this -> value + $ other -> value ) ; }
Add two Sizes and return the sum.
Add two Sizes and return the sum .