toActionInput evaluates undefined

[kschweppe]

Consider the following example:

instance HyperView TestView es where
    data Action TestView = Test Int Int

view :: View TestView ()
view = dropdown (\x -> Test x 1) 0 none

In this case, toActionInput will evaluate undefined in toAction (act undefined), which only seems to work if the supplied argument is the last one for the given action, i.e., \x -> Test 1 x works but \x -> Test x 1 does not.

[seanhess]

@kschweppe - That's unfortunate. Whether or not we could somehow fix it being evaluated, the whole idea assumes a partially applied constructor. (It drops the last argument using init vals). Previous versions were text only, and used a delimiter like "%%HYP_INPUT%%" which could be cleaned up on render.

There's probably some clever solution here, but I can't think of it. We could switch to error instead of undefined and give the user a runtime error instead of an undefined, explaining they need to avoid applying the arguments out-of-order, but that's no fun at all.