Update task-expressions.md

[Lanayx]

Added and! section

Summary

Describe your changes here.

Relates to dotnet/fsharp#18451

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[BillWagner]

@T-Gro Can you give this a look?

[baronfel]

This LGTM - @Lanayx would it be possible to link to the RFC/spec for how this is implemented so that users that want to understand the concurrency semantics can learn more? Something like:

For more details about this built-in support for concurrency, see RFC-1234

Also, there's a limitation involved with this current implementation, right? Might be good to have a Note: section outlining that rough edge.

[Lanayx]

This LGTM - @Lanayx would it be possible to link to the RFC/spec for how this is implemented so that users that want to understand the concurrency semantics can learn more? Something like:

It's possible of course, I thought about it, but I'm not sure it's needed in place. I see this page as a reference for "how to use it", rather than "how does it work inside", so the link to implementation is a bit off topic in my view. Maybe adding to the links list at the bottom is a better option?

Also, there's a limitation involved with this current implementation, right?

No, there are no limitations, only space to improve performance in future. I don't think we should mention it on this page.

[T-Gro]

Agree with @Lanayx , we don't put RFC details (sometimes very low level details) into docs ;; except for a footer as related links.

[BillWagner]

Thanks @Lanayx

This LGTM. I'll after making a minor lint fix.