This functionality is only applicable when building a QPL query manually, if you want custom operators for the parser, you will need to generate a new grammar in which case, please contact the development team
PyQPL allows to include custom operators in your query and even add translation for these. There are 2 ways to make use of a custom operator, besides the translation process, one quick and simple and another one defining the operator with a class.
For both methods we need to make use of the op function in the QPL
Simple Custom Operator
Overview
Content Tools