MGLStyleAttributeFunction.functionType should be MGLStyleAttributeFunctionType

[1ec5]

MGLStyleAttributeFunction.functionType should be of type MGLStyleAttributeFunctionType, not NSNumber. The style specification allows the type property to be omitted, but the value is actually exponential (MGLStyleAttributeFunctionTypeExponential) or interval (MGLStyleAttributeFunctionTypeInterval) by default, depending on the property, and it’s meaningless for a function to have no type. So there’s no need for a nullable object here.

/cc @frederoni

[frederoni]

type is omitted or not yet implemented in function.hpp so I suggest we remove MGLStyleAttributeFunction.functionType and the other unused types until we can make use of them.

[1ec5]

Is there a ticket tracking that core work? Seems like it'd be important for style specification compliance and GL JS parity.

[1ec5]

Per @lucaswoj, function types are only relevant for property functions, so we’ll only need SDK support for them once #4860 is implemented.