public function where($field, $value,$opposite = false)
    {
        return $this->filter(function ($item) use($field,$value,$opposite){

            $method = $this->concatGet($field);

            $pass = $item->$method() == $value;

            return $opposite ? !$pass : $pass;
        });
    }
public function where($field, $value,$opposite = false)
    {
        return $this->filter(function ($item) use($field,$value,$opposite){

            $method = $this->concatGet($field);

            $pass = $item->$method() == $value;

            return $opposite ? !$pass : $pass;
        });
    }
public function where ( $ field , $ value , $ opposite = false ) { return $ this -> filter ( function ( $ item ) use ( $ field , $ value , $ opposite ) { $ method = $ this -> concatGet ( $ field ) ; $ pass = $ item -> $ method ( ) == $ value ; return $ opposite ? ! $ pass : $ pass ; } ) ; }
search the value in the collection in a specific field.

@param $field
@param $value
@param bool $opposite
@return ServiceCollection
search the value in the collection in a specific field .