It now avoids unnecessary re-renderings, by comparing equality
with all its arguments, and by using a Reaction to filter out
only the changes that affects its value.
This also adds an optional setter callback, that is called instead
updating the parent atom directly.
This makes most comparisons faster, and should result in fewer
re-renderings. And it should be a lot easier to explain and
reason about than the old heuristics.
It also makes it much easier to make custom objects, e.g. different
cursor implementations, avoid unnecessary re-renderings.
The main downside is that it is no longer possible to pass infinite
sequences to components.
The new names correspond to changes in React in 0.12.0.
Both render-component and render-component-to-string are kept for
backward compatibility.
Call React.render etc to avoid deprecation warnings from React.
Adds RCursor type: wraps Reagent's RAtom along with a path that provides focus into a specific part of that atom.
Adds reagent.ratom/cursor as a constructor for the RCursor type.
Adds reagent.core/cursor as the public API. This can be called with just a path, and returns a function that accepts a Reagent atom, or with both a path and an atom.
Dereferences of a cursor behave like get-in on the underlying atom with the specified path.
If you reset! a cursor, it behaves like a swap! assoc-in on the underlying atom. If swap! a cursor, it behaves like a swap! update-in on the underlying atom.
This is actually a bug in ClojureScript
(http://dev.clojure.org/jira/browse/CLJS-777). In regular Clojure a
`MultiFn` is `ifn?`, but in ClojureScript it wasn't. The bug is now
fixed
(525154f2a4)
but not yet released.
This code can be reverted after Reagent's ClojureScript version is
updated.