Core FAQ

Should applications use Core directly?

Use Core directly for shared policy libraries, adapter development, non-UI validation, or framework-free forms such as the Vanilla Showcase. Use Angular or React adapters when you need framework lifecycle integration and display helpers for application forms.

Does Core mutate the model?

Validation metadata is written to the model so adapters can read a consistent result shape. Domain values are not changed by validators.

Are policies framework-specific?

No. A policy that imports only Core contracts can be reused by Angular, React, and plain TypeScript callers.

Can rules be asynchronous?

Yes. Use userDefined and return a promise or observable-like result when the adapter supports asynchronous execution.

Why do optional email fields pass when empty?

Format rules skip empty values. Add isRequired when the field must be present.

How should dynamic fields work?

Generate policy metadata from the same field definitions used to render the UI. Replace or unregister old generated policies when fields are removed.