Logic Expression Reference

Logical expressions allow you to create dynamic, responsive surveys by evaluating respondent answers in real-time. You can use these expressions to control visibility, requirement, and validity of form elements.

This reference section is divided into three parts:

Introduction to Logic Expressions

Learn the basic syntax, how to bind survey fields to your expressions via drag-and-drop, and the standard comparison and logical operators.

Advanced Logic Expressions

Explore more complex capabilities, including mathematical (binary) operations, the ternary operator for conditional branching, and custom transforms like length.

Jexl Syntax Reference

A technical reference for the underlying Jexl library, covering native types, identifiers, collection filtering, and advanced syntax rules.