Brendan Hansknecht (Jul 09 2024 at 01:05): Brendan Hansknecht (Jul 09 2024 at 01:05):I guess you can't always use crash and put in a todo when abilities are involved:
── TYPE MISMATCH in MsgPack.roc ────────────────────────────────────────────────
This specialization of i16 is overly general:
55│ encodeI16 = \_ -> crash "todo"
^^^^^^^^^
This value is a declared specialization of type:
* -> *
But the type annotation on i16 says it must match:
I16 ->
FutureEncode.FutureEncoder state where state implements FutureEncode.FutureEncoderFormatting
Note: The specialized type is too general, and does not provide a
concrete type where a type variable is bound to an ability.
Specializations can only be made for concrete types. If you have a
generic implementation for this value, perhaps you don't need an
ability?
Tip: Type comparisons between an opaque type are only ever equal if
both types are the same opaque type. Did you mean to create an opaque
type by wrapping it? If I have an opaque type Age := U32 I can create
an instance of this opaque type by doing @Age 23.
hm yeah I'm not sure if that's avoidable :thinking:
Brendan Hansknecht (Jul 09 2024 at 01:23):Luckily, roc is happy turning function prototypes into runtime errors:
encodeI16 : I16 -> FutureEncoder MsgPack
# No definition
ha, nice!
Brendan Hansknecht (Jul 09 2024 at 01:25):Trying to make sure that my gist on the new encoders is correct
Richard Feldman (Jul 09 2024 at 01:25):hm, if that's the case, I'm kinda surprised it accepts one but not the other :thinking:
Brendan Hansknecht (Jul 09 2024 at 01:25):Yeah, probably should be printing out a warning with taht
Brendan Hansknecht (Jul 09 2024 at 01:25):it's probably a bug that it just emits a runtime error and no warning
Richard Feldman (Jul 09 2024 at 01:25):@Ayaz Hafiz might know why this works :sweat_smile:
Richard Feldman (Jul 09 2024 at 01:26):I guess it's because in the annotated version it's a less general type
Richard Feldman (Jul 09 2024 at 01:26):but it's still surprising to me that it works
Ayaz Hafiz (Jul 09 2024 at 05:03):yes, that's why
Ayaz Hafiz (Jul 09 2024 at 05:03):the annotation forces the type
Last updated: Jul 26 2025 at 12:14 UTC