"Clojure supports sophisticated runtime polymorphism through a multimethod system that supports dispatching on types, values, attributes and metadata of, and relationships between, one or more arguments."
Source: http://clojure.org/multimethods I guess I should have started with the docs. The possibilities are now infinite as far as sharing transforms across paths and working with "state meta data" ... The thing about "relationships between" is something I still have to internalize. Will hack on it and put together a full repo demonstrating the power of combining Reagent's cursor function with Clojure's multi-methods, and provide example use cases (the one I started with has to do with transforming ajax response upon storing it in app state) :) On Mon, Apr 27, 2015 at 7:16 PM, Marc Fawzi <[email protected]> wrote: > Hi guys, > > During our last SF Reagent meetup > (http://www.meetup.com/Reactive-ClojureScript/events/221710610/ -- I > still owe you a professionally produced video), there was this interesting > perception that cursors in Reagent were just pointers and therefore > couldn't implement any transformation on the data. Maybe I misunderstood > the context but that's what I recall being said. > > So I put together a quick example of how to implement inward and outward > transforms on app state atom using Reagent cursors, which are quite > powerful. > > Disclaimer: I literally just learned about multi-methods a couple days ago > so I'm pretty sure I'm misusing them in some way, but that shouldn't take > away from the basic fact that we can do inward and outward transformations > on state using just cursors. > > I've asked a few more experienced folks to educate me on the various > mistakes I've made and explain any failings of this abstraction or help > improve it. I'll post any updates and contributions to this thread, or you > may post your own right here. > > The example is here: > > https://gist.github.com/idibidiart/2b3aa1594ce707227b96 > > State: > (def state (atom {:parentX { > :childX 42 > } > :parentY { > :childY 23 > }})) > > Console log: > in-transform changes actual value of cursor: node pointed to by cursorX is > now 12 (2X value) after being set to 6 > {:parentX {:childX 12}, :parentY {:childY 23}} > > out-transform changes return value: cursorY returns 2X its actual value of > 23, --> 46 > > out-transform doesn't change actual value of cursor: node pointed to by > cursorY still shows 23 as value > {:parentX {:childX 12}, :parentY {:childY 23}} > > You can still get at cursorY's actual value via @cursorY-No-Transform 23 > > Just trying to understand things... > > Thank you, > > Marc > -- Note that posts from new members are moderated - please be patient with your first post. --- You received this message because you are subscribed to the Google Groups "ClojureScript" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/clojurescript.
