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  • Glasgow Haskell Compiler
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  • #9840

Closed
Open
Opened Nov 27, 2014 by Adam Gundry@adamgundryDeveloper

Permit empty closed type families

At the moment, closed type families without any equations fail with a parse error. In addition, they cannot be created by TH (see #8028 (closed)). Would it be possible to permit these instead?

My use case is in my typechecker plugin for units of measure, where I want to add new type-level operators without any equational theory (because it will be supplied by the plugin) and without users having the ability to introduce their own type family instances.

Trac metadata
Trac field Value
Version 7.8.3
Type FeatureRequest
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler (Type checker)
Test case
Differential revisions
BlockedBy
Related
Blocking
CC goldfire
Operating system
Architecture
Assignee
Assign to
8.0.1
Milestone
8.0.1 (Past due)
Assign milestone
Time tracking
None
Due date
None
Reference: ghc/ghc#9840