public function setValueMutator(callable $callback) : self
    {
        $this->valueMutator = $callback;
        $this->value = ($this->valueMutator)($this->value);
        return $this;
    }
public function setValueMutator(callable $callback) : self
    {
        $this->valueMutator = $callback;
        $this->value = ($this->valueMutator)($this->value);
        return $this;
    }
public function setValueMutator ( callable $ callback ) : self { $ this -> valueMutator = $ callback ; $ this -> value = ( $ this -> valueMutator ) ( $ this -> value ) ; return $ this ; }
Set callback function for changing values before compare.

@param callable $callback
@return InNestedArray
Set callback function for changing values before compare .