LightCode Course - Chapter 12: Data Validation and Consistency

Learning Outcomes: • Identify and describe the basic data types used in LightCode (string, number, boolean, list, date), along with their default icons and typical interface behaviors. • Recognize how UI widgets (e.g. checkboxes, picklists) are automatically generated from declared types and how they support implicit type-level validation in forms and blocks. • Define structured data models using object classes and attributes, understanding how these structures drive interface generation and constrain input without custom logic. • Distinguish between structural consistency (valid types and required presence) and behavioral consistency (valid transitions, logical flow, and object state coherence). • Apply validation logic through state-dependent methods, using Python assert statements to enforce domain-specific rules at the right time. • Write and interpret embedded test methods to simulate behaviors and verify system correctness before user interaction. • Understand how validation is distinct from persistence, and how consistency can be modeled and tested without relying on database schemas. • Evaluate and resolve validation issues by interpreting visual feedback, error messages, and structured test output in the LightCode platform. • Appreciate the value of progressive validation—building consistency step by step—as a teachable and scalable design pattern for low-code apps.