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Comment by sklogic | Hacker News Reader

Of course I can. If my tools are communicating with my compiler, they know everything it knows. I have a single tiny generic Emacs mode (and a similar Visual Studio extension) that handles all the languages designed on top of my extensibility framework.

It's trivial. Any PEG parser I add on top automatically communicates all the highlighting, indentation data and all that to the tools (and it's inferred from the declarative spec, no additional user input is required). Underlying typing engines do the same, for the nice tooltips and code completion. The very compiler core doest the same with all the symbol definitions, dependencies, etc. Easy.

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This sounds very interesting :) And I think Colin Flemming is doing something similar in Cursive? In any case, I'd like to see more of what you are talking about - do you have any more documentation of it, a writeup, blog post or video?

If I understand it correctly, Cursive is something different, they don't want to run an inferior Clojure image (unlike Slime, for example), but reproducing a lot of Clojure functionality with their massively complex static analysis tools. But I might get it wrong, all the information I have about Cursive came from one of its advocates who is very aggressively against the very idea of an inferior REPL for an IDE.

I've got some code published, but not that much in writing, planning to fix it some time later. See the stuff at my github account (username: combinatorylogic). Relevant things there are Packrat implementation, literate programming tools and an Emacs mode frontend.

Exactly! You end up defining your macros in a particular restricted subset of lisp, and your tooling for Emacs and Visual Studio has to know about that particular subset. Other people writing similar macros will no doubt have their own, subtly different subset, and their own integrations for their subset. But since your way of writing declarative specs for language customization isn't standardized, you can't use each other's tool integrations.

The way you express DSLs is something that needs to be understood by language tooling, so it belongs in the language spec.

No. Tools do not know anything about the restrictions. In fact they work with a wide range of languages, not just lisp. The only "restriction" is a protocol, built into the macro expander, syntax frontend and compiler core.

So, in your rot13 example compiler would rat all the new identifiers with their origins to the tools.

> So, in your rot13 example compiler would rat all the new identifiers with their origins to the tools.

How can the compiler know which identifier connects to which origin, unless because the macro complied with some standard/restriction/protocol? From a certain perspective all I'm suggesting is making these protocols part of the language standard - that is, define the DSL that's used to define DSLs, rather than allowing macros to consist of arbitrary code.

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