Enumeration number problem

[OnkelTem]

For some reason numbers are not allowed in enumerations:

const ordersRequest = types.model({
  paymentPeriod: types.optional(types.array(types.enumeration('PaymentPeriod', [15, 30])), [15]),
})

i.e. for a type like: (15 | 30)[].

As far as I understand, I have to use types.union for this:

const ordersRequest = types.model({
paymentPeriod: types.optional(types.array(types.union(types.literal(15), types.literal(30))), [15]),
})

Can numbers be added to enumerations?

[thegedge]

I can't see why we shouldn't support that! :)

But it is indeed always forced into a string enumeration now because of this line:

mobx-state-tree/src/types/utility-types/enumeration.ts

Line 44 in ab45ead

const type = union(...realOptions.map(option => literal("" + option)))

I did some digging and found that it's been that way since its introduction, with no explanation as to why we did that: #263

My gut is saying there's no particular reason why this was done, but we'll have to investigate it.