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by dom96 2938 days ago
> Nim macros are not quite at the Lisp level, but they are extremely powerful.

I'm not fully familiar with Lisp macros so I'm curious, what is Nim missing that Lisp has in terms of metaprogramming?

1 comments

Two things in common use:

Lisp has reader macros that can alter lexical analysis and parsing; correct me if I am wrong, but I think that’s not possible in Nim. E.g. things like JSX are trivial to implement in Lisp.

Also, lisp macros let you e.g. write new control structures with multiple “body” parts - iirc, in nim only the last untyped macro arg can be a code body (you can put a block in parantheses, but that’s not as elegant)

I’m sure there’s other stuff that fexprs and other [a-z]exprs can do that nim can’t, but i’Ve never seen them in use (or used them myself)

Also, personally I think Nim’s model is more practical; lisp’s power essentially requires lispy or REBOLy syntax to be usable. Nim is pascalythonesque, and though complex is not complicated; much like Python, and unlike C++, you can make use of the ecosystem without being afraid of obscure details biting you - but it has all the capabilities when you need them.