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re-frame 2024-12-13
For a materialized view using the shorthand form, is it possible to pass a query variable to the input signal?
something like
(reg-sub
:id
;; input signals
:<- [:a entity-id] ;; means (subscribe [:a] is an input)
:<- [:b 2] ;; means (subscribe [:b 2] is an input)
;; computation function
(fn [[a b] entity-id other-query-v]
(calculate-it a b)))
thogha 2024-12-13T23:52:49.061279Z
Given an event handler with two effects, where the second effect depends on the first completing, can the following pattern be relied upon?
(rf/reg-event-fx
::dispatch-events-sequentially
(fn [_ _]
{:fx [[:dispatch [::first-event]]
[:dispatch [::depends-on-first-completing]]]}))(rf/reg-event-fx
::depends-on-first-completing
(fn [_ _]
{}))
(rf/reg-event-fx
::first-event
(fn [_ _]
; calculate something
{:fx [[:dispatch [::depends-on-first-completing]]]}))
(rf/reg-event-fx
::dispatch-events-in-chain
(fn [_ _]
{:fx [[:dispatch [::first-event]]]}))p-himik 2024-12-14T09:58:58.019899Z
The events will be handled in the right order. In fact, the :fx effect handler checks that its argument is sequential.
But if ::first-event uses :dispatch or some other "happens later" effects, then of course ::depends-on-first-completing will not see the results of those effects. That's why I mentioned before that "util" events become harder to use the more you rely on them.