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I wonder if there is a relationship between untyped/typed code quotations in F# and the hygiene of macro systems. Do they solve the same issues in their respective languages or are they separate concerns?
Quotations are a form of meta-programming. They allow you to manipulate abstract syntax trees programmatically, which can be in turned spliced into code, and evaluated.
Typed quotations embed the reified type of the AST in the host language’s type system, so they ensure you cannot generate ill-typed fragments of code. Untyped quotations do not offer that guarantee (it may fail with a runtime error).
As an aside, typed quotations are strongly similar to Template Haskell quasiquotations.
Hygenic macros in Lisp-like languages are related, in that they exist to support meta-programming. The hygiene however is for simple name capture confusion, something that typed quasi quotations already avoid (and more).
So yes, they are similar, in that they are mechanisms for meta-programming in typed and untyped languages, respectively. Both typed quasi quotes and hygenic macros add additional safety to fully untyped, unsound meta programming. The level of guarantee they offer the programmer though is different. The typed quotes are strictly stronger.