Schema

The Schema module contains primitive schemas, collection and recursion combinators, union constructors, and the operations that parse or check a completed declaration.

Use Schema.parse for untrusted Data. It decodes fields, applies constraints and refinements, accumulates independent failures as SchemaErrors, and invokes the model constructor only after the fields succeed.

Use Schema.check when a typed value came from another constructor, an import, or a database mapper. It reads the declared fields back from the value and checks them.

The same model constructor runs again, so cross-field invariants are checked too. Success returns the checked value itself.

The Schema quickstart introduces the workflow. The member catalogue below is the complete construction and execution vocabulary.