Build APIbldr
BuildEntry
A member's build function: given its root Scope, declare what it
type in bldr
A member's build function: given its root Scope, declare what it
builds.
It was once handed a BuildContext carrying the registration methods. Those
live on Scope now — a scope already knows where it is, which is what a
target's name is made of — and the context had nothing else on it that any
build in this repo used.
type BuildEntry = (…) => …See Scope.