This commit adds subtree memoization to Dioxus.
Subtree memoization is basically a compile-time step that drastically
reduces the amount of work the diffing engine needs to do at runtime by
extracting non-changing nodes out into a static "template." Templates
are then understood by the various renderers in the ecosystem as a
faster way of rendering the same items.
For example, in the web, templates are simply a set of DOM Nodes created
once and then cloned later. This is the same pattern frameworks like Lithtml
and SolidJS use to achieve near-perfect performance.
Subtree memoization adds an additional level of complexity to Dioxus. The RSX
macro needs to be much smarter to identify changing/nonchanging nodes and
generate a mapping between the Template and its runtime counterparts.
This commit represents a working starter point for this work, adding support
for templates for the web, desktop, liveview, ssr, and native-core renderers.
In the future we will try to shrink code generation, generally improve
performance, and simplify our implementation.
This change switches back to the original `ctx<props>` syntax for
commponents. This lets lifetime elision to remove the need to match
exactly which lifetime (props or ctx) gets carried to the output. As
such, `Props` is currently required to be static. It *is* possible to
loosen this restriction, and will be done in the future, though only
through adding metadata about the props through the Props derive
macro. Implementing the IS_STATIC trait is unsafe, so the derive macro
will do it through some heuristics.
For now, this unlocks sharing vnodes from parents to children, enabling
pass-thru components, fragments, portals, etc.
