I want to add the :disabled attribute only if the value in an atom is empty. In Hoplon, I can conditionally set attributes like this:

(button
  :do-attr (cell= {:disabled (string/blank? cell-with-contents)})
  "Get stuff")

@ulsa you should be able to do more or less the same thing with reagent: [:button {:disabled (string/blank? @some-atom)} “Get stuff”]

Tried that. Can't seem to get the dynamicity working.

can you gist the code?

I want the attribute if true, otherwise I don't want it at all.

But I end up with disabled="" regardless

@ulsa I find reagent mostly behaves the same for {:a nil} and {} in which case I write code like {:my-attr (when pred? “some value”)}

if not then (cond-> {} pred? (assoc :my-attr “some value”))

you can also do something like (when-not (string/blank? …) {:disabled true})

where?

[:button (when-not (string/blank? …) {:disabled true}) “Get stuff”]

I have more attrs though

(cond-> {} pred? (assoc :my-attr “some value”))

yes, something like @colin.yates is suggesting would work well then

or (merge my-attrs (when-not (string/blank? …) {:disabled true}))

nope

will this code be run whenever the dereferenced atom changes?

it should yes, if you’re using reagents version of atoms

everything else works, just not disabled

the atom is updated when I type into the textfield, but disabled is always = ""

that’s very strange

my fault, used reagent atom in other files, but not this one

problem hopefully solved then

will clean up and report what works

cond-> works

regular boolean pred works; it goes away on false

when works too; it goes away on nil

thanks guys

btw, having a good time diving into reagent for the first time

yeah, reagent is really easy to work with

btw - you might want to take a look at re-frame if you like reagent

ok, will do that; I bootstrapped using luminus +cljs

so reaction is like cell=?

@ulsa yes, very similar intent.

BTW, depending on your requirements, as well as re-frame, you might like re-com

is there anything like hoplon's :do-toggle?

I suppose {:style {:display (if pred "block" "none")}} can do it.