15 — Primitives and the registry: a promise, and who checks it

After this lesson you will be able to say what a deployment's registry actually bounds and what it does not; name the five places a primitive's registration is acted on, give the different question each one answers, and say which single one of the five prevents rather than detects; explain why declaring a prop schema is mandatory and why declaring one still restricts nothing unless the author asked it to; say why building a registry is forbidden from calling a component and what that forced into a separate function; give the rule for what the audit is allowed to conclude from one render and what it is not; and say what the audit has in common with the Gate about the kind of thing a library is willing to decide.

Prerequisites: 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, 12, 13, 14. The ones this lesson leans on hardest are 09, 12 and 14.

Lesson 14 ended on a loose end and named it:

The renderer's whole dependency on a registry is one lookup — resolve(type), returning a component or nothing. That was the right size for lesson 14 and it is a lie of omission. Behind the lookup is a set of promises somebody made about a component, and this lesson is about what those promises are worth.