xhp VS whichever-compiles

It’s cool that you can express this sort of structure in Lisp without any change to the language. This contrasts to extensions to other languages that allow an XML-like syntax. For example JSX for JavaScript [1], XHP for PHP [2], and XML Literals for VB.NET[3].

[1]: https://reactjs.org/docs/introducing-jsx.html

[2]: https://github.com/phplang/xhp

[3]: https://docs.microsoft.com/dotnet/visual-basic/programming-g...

I don't think "Rustaholics" need to be told about this? See for example https://github.com/m-ou-se/whichever-compiles

You can't build an IDE that definitely just "understands Rust macros" since procedural macros in particular are in effect modifying your compiler. Maud is a proc macro.

Mara's whichever_compiles! macro for example: https://github.com/m-ou-se/whichever-compiles -- that macro is forking your compiler to try out all the branches and throwing away branches which caused a compile error.

Clearly your IDE should throw its hands up and say, I don't understand what this does, I give up.

In general doing something useful with Rust macros is a more tractable problem for an IDE than say the C pre-processor, because Rust's macros have a stronger syntax, but the proc macro is potentially much too powerful / dangerous to try to evaluate.