Issue with type = ... and pattern matching

[geraldus]

Hello buddies! Sorry if I stupid and annoying.
Consider following code, which works:

I have small helper:

fromNullable :: Nullable a -> a
fromNullable (Nullable smth) = smth

Every time before I use it I must be sure if value is not Null. That's not big deal.

snap :: String -> Fay (Nullable Fragment)
snap = ffi "Snap(%1);"

When I snaping back a real object but not Null then it is OK to pass the result to fromNullable and unwrap Fragment.

Then I wanted to make my code a bit cleaner and finished with this:

type NullFragment = Nullable Fragment
snap :: String -> Fay NullFragment

But this time I'm getting a runtime exception unfortunately, because in this case I could not pattern match (Nullable smth) anymore.

Uncaught unhandled case in fromNullable

Is this a bug or just another not implemented feature?

[bergmark]

Resolving type aliases in the FFI hasn't been implemented yet, #185.

On Thu, Jan 9, 2014 at 11:04 PM, Артур Файзрахманов <
[email protected]> wrote:

Hello buddies! Sorry if I stupid and annoying.
Consider following code, which works:

I have small helper:

fromNullable :: Nullable a -> a
fromNullable (Nullable smth) = smth

Every time before I use it I must be sure if value is not Null. That's
not big deal.

snap :: String -> Fay (Nullable Fragment)
snap = ffi "Snap(%1);"

When I snaping back a real object but not Null then it is OK to pass the
result to fromNullable and unwrap Fragment.

Then I wanted to make my code a bit cleaner and finished with this:

type NullFragment = Nullable Fragment
snap :: String -> Fay NullFragment

But this time I'm getting a runtime exception unfortunately, because in
this case I could not pattern match (Nullable smth) anymore.

Uncaught unhandled case in fromNullable

Is this a bug or just another not implemented feature?

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Reply to this email directly or view it on GitHubhttps://github.com//issues/380
.

[bergmark]

I'll close this in favor of that ticket, please subscribe to that one for updates.