src/Primitive/String/String.php
public function titleize($ignore = null)
    {
        return new static(StaticStringy::titleize($this->string, $this->getArrayable($ignore)));
    }
public function titleize($ignore = null)
    {
        return new static(StaticStringy::titleize($this->string, $this->getArrayable($ignore)));
    }
Return a trimmed string with the first letter of each word capitalized.
Ignores the case of other letters, preserving any acronyms. Also accepts
an arrayable, $ignore, allowing you to list words not to be capitalized.

@param mixed $ignore
@return static