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hashes / missing names for types in both scratch file and codebase
Describe and demonstrate the bug
When modifying a type, it is easy to end up with an error message that includes a hash and doesn't show a clear relationship to the type in the scratch file/codebase.
scratch/main> builtins.merge
Done.
type User = User Text
User.email : User -> Text
User.email = cases User e -> e
sendEmail : Text -> User -> {IO} ()
sendEmail msg user =
Debug.trace ("sending to " ++ email user) msg
Loading changes detected in scratch.u.
I found and typechecked these definitions in scratch.u. If you
do an `add` or `update`, here's how your codebase would
change:
⍟ These new definitions are ok to `add`:
type User
User.email : User -> Text
sendEmail : Text -> User ->{IO} ()
scratch/main> update
Done.
type User = User Text Nat
sendEmail : Text -> User -> {IO} ()
sendEmail msg user =
Debug.trace ("sending to " ++ email user) msg
🛑
The transcript failed due to an error in the stanza above. The error is:
The 1st argument to `email`
has type: User
but I expected: #3otongueea
3 | sendEmail : Text -> User -> {IO} ()
4 | sendEmail msg user =
5 | Debug.trace ("sending to " ++ email user) msg
Environment (please complete the following information):
ucm --version842635bbc
I think improving the error message would be pretty simple to implement, and get us maybe 50-60% the way towards a better solution:
The 1st argument to `email`
has type: User
but I expected: User#3otongueea (shadowed by scratch.u)
3 | sendEmail : Text -> User -> {IO} ()
4 | sendEmail msg user =
5 | Debug.trace ("sending to " ++ email user) msg
Maybe "(in scratch file)" and "(in branch)"; they can both have hashes too.
I see, the issue is that we basically need to propagate, as if for an update, before or while we type-check, because the current type check errors are arguably out of date.
We could probably speed up type-checking in general if we had a way to do it in a dependency order, and fix this issue in the process.