Vladimir Shchur

TS provides [Omit ](https://www.typescriptlang.org/docs/handbook/utility-types.html#omittype-keys)construct for type-level `without`

For TS I think it is ok, since spread is only for instance level there and constructs are for type level. For F# we are planning to use spread everywhere,...

While someone will be creating an RFC for this, specifically for spreading on record types, there will be a choice - to copy attributes together with fields definitions or not....

Seems to be similar to https://github.com/fsharp/fslang-suggestions/issues/625

After thinking it over I've got one concern - in cases where I mostly don't specify types it will default to list which is a bad default (from performance perspective)...

@T-Gro thanks, however I think it is expected that for tuples regular null checks should work. It's also promised in the [release post](https://devblogs.microsoft.com/dotnet/nullable-reference-types-in-fsharp-9/#handling-nulls): > The same technique works for matching...

Yes, I understand that there is a workaround with active patterns (updated the description). The question is - should the tuple match limitation be fixed or mentioned in documentation? I...

Another case - using [UnsafeAccessorAttribute](https://github.com/dotnet/runtime/issues/81741) for fast access to member attributes. It was one of the prominent performance topics in [.NET9](https://devblogs.microsoft.com/dotnet/performance-improvements-in-net-9/#reflection) and [.NET10](https://devblogs.microsoft.com/dotnet/performance-improvements-in-net-10/#reflection), but is still unusable from F#.

@En3Tho I was under impression that this attribute implies source generation :) Created a suggestion https://github.com/fsharp/fslang-suggestions/issues/1451

Thank you for the suggestion, will you be able to submit a PR with updates?