src/Base/NoKeysTrait.php
public function add($value): bool
    {
        if ($this->has($value)) {
            return false;
        }

        $this->set($value);

        return true;
    }
public function add($value): bool
    {
        if ($this->has($value)) {
            return false;
        }

        $this->set($value);

        return true;
    }
public function add ( $ value ) : bool { if ( $ this -> has ( $ value ) ) { return false ; } $ this -> set ( $ value ) ; return true ; }
Adds a new item to the collection.

@param mixed $value

@return bool true on success, false if the item already exists.
Adds a new item to the collection .