src/DMS/Filter/Rules/Callback.php
public function getInputType()
    {
        switch (true) {
            case $this->callback instanceof Closure:
                return self::CLOSURE_TYPE;

            case is_callable($this->callback, false):
                return self::CALLABLE_TYPE;

            case is_string($this->callback):
                return self::SELF_METHOD_TYPE;
        }

        throw new InvalidCallbackException(
            "The input provided for Callback filter is not supported or the callable not valid.
            Please refer to the class documentation."
        );
    }
public function getInputType()
    {
        switch (true) {
            case $this->callback instanceof Closure:
                return self::CLOSURE_TYPE;

            case is_callable($this->callback, false):
                return self::CALLABLE_TYPE;

            case is_string($this->callback):
                return self::SELF_METHOD_TYPE;
        }

        throw new InvalidCallbackException(
            "The input provided for Callback filter is not supported or the callable not valid.
            Please refer to the class documentation."
        );
    }
public function getInputType ( ) { switch ( true ) { case $ this -> callback instanceof Closure : return self :: CLOSURE_TYPE ; case is_callable ( $ this -> callback , false ) : return self :: CALLABLE_TYPE ; case is_string ( $ this -> callback ) : return self :: SELF_METHOD_TYPE ; } throw new InvalidCallbackException ( "The input provided for Callback filter is not supported or the callable not valid.
            Please refer to the class documentation." ) ; }
Figures out which type of input was provided

@return string
@throws \DMS\Filter\Exception\InvalidCallbackException
Figures out which type of input was provided