cannot extend generic class  #1929

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1. carsakiller commented on Feb 20, 2023

   

   carsakiller

   on Feb 20, 2023

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   There are just so many issues about generics and generic classes 😰

   Going to close this one as a duplicate of #1863 or #1378
2. carsakiller

   added

   duplicateThis issue or pull request already existsThis issue or pull request already exists

   feat/genericRelated to generic emulation featureRelated to generic emulation feature

   on Feb 20, 2023
3. carsakiller

   closed this as not plannedon Feb 20, 2023
4. somebody1234 commented on Feb 20, 2023

   

   somebody1234

   on Feb 20, 2023

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   @carsakiller saw those from the generics super issue, but afaict this is a different issue
5. somebody1234 commented on Feb 20, 2023

   

   somebody1234

   on Feb 20, 2023

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   the issue here is : Foo<t> just flat out doesn't work
6. carsakiller commented on Feb 20, 2023

   

   carsakiller

   on Feb 20, 2023

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   Yes, but the bottom line is really that --- @class Foo<t>: { a: t } doesn't work because generic classes are not supported. The ---@class Child: Parent syntax is supported elsewhere, so when generic classes are implemented, Child : Parent<T> should also work. This is the first time I have seen this syntax mentioned though, I think, so I'll add it to the list just so we can make sure it receives some attention.

   Just trying to keep things organized—there are so many similar issues with slight variations 😄
7. carsakiller

   reopened this on Feb 20, 2023
8. somebody1234 commented on Feb 20, 2023

   

   somebody1234

   on Feb 20, 2023

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   i was assuming it does work though:

   • the docs mention it
     • (the builtin table and array are generic classes afaict)
   • it works if you're not doing : Foo<t>

   
9. carsakiller commented on Feb 20, 2023

   

   carsakiller

   on Feb 20, 2023

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   I see, I thought the generic class was not working when inheriting { a: t } as well. It seems it does though.

   --- @class Foo<t>: { a: t; }
   
   ---@type Foo<integer>
   local x
   print(x.a) -- Type is integer
   
   
   ---@class Bar : Foo<integer>
   
   ---@type Bar
   local y
   print(y.a) -- undefined field `a`
10. ian-pascoe

    added a commit that references this issue on Jan 11, 2026

    fix: support generic class inheritance with type arguments

    ...

    This issue will close once commit 5d44a98 is merged into the 'master' branch.

    5d44a98
11. sumneko

    closed this as completedin 5d44a98on Jan 19, 2026