Host and Scope
Status: implemented Core model.
<serc-rod> is the Core host. Ordinary HTML outside
a host remains outside its ownership. A nested host is independent: its
parent does not treat the child host's internal template as part of the
parent's template.
Each host renders against a scope object. Host data is the primary
expression scope and is also $data. $root
refers to root data; $parent refers to a nearest parent
scope when one exists. *let, *for, and
*each can add local subtree values without mutating host
data unless an expression explicitly writes.
Root-host boundary
A root host has no parent scope to traverse. Do not use
$parent there as an application value. The runtime
specification deliberately does not make the exact fallback
representation (undefined, null, or an empty
value) a dependency for templates.
Evidence
Status: implemented.
Evidence: docs/spec/runtime.md Sections 2, 4, 6, and 17;
dist/sercrod.js; canonical manual
dist/man.json.