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I'm mostly arguing against extensive use of meta programming, which is promoted as one of the main reasons to view data as code, as meta programming is inherent

I'm mostly arguing against extensive use of meta programming, which is promoted as one of the main reasons to view data as code, as meta programming is inherently disadvantaged for automated tooling. Formulated as a trade-off: When I have to choose, I prefer richness of IDE (and other tooling) automation to program creation automation that I write myself (i.e. meta programming). This trade-off is not restricted to Lisp, but also applies to e.g. C++ template meta programming. Compilers have gotten betters with templates, but still debugging the more advanced usages of templates can become hellish. Codifying the features the meta programming supplies in the language itself or in well supported libraries means that error messages get better and many usage scenarios are documented on Stackoverflow. I don't doubt your experience regarding Clojure vs JavaScript code bases, but this probably has to do with other reasons than the meta programming the original blog post is about?

wtetzner 6y ago
> I'm mostly arguing against extensive use of meta programming, which is promoted as one of the main reasons to view data as code, as meta programming is inherently disadvantaged for automated tooling. Which is weird, because in most Lisps meta programming happens at compile time. It should be possible for tooling to just show you the expansion of any given macro invocation. In fact, when I used Clojure a decade ago, there was an Emacs command that would expand the macro invocation under your cursor, so you could see what code was actually being generated. So I don't really think that's a fundamental limitation. I suspect it's more related to the fact that Lisps aren't especially popular, and don't get the attention from tooling that other languages do. > Codifying the features the meta programming supplies in the language itself or in well supported libraries But without the meta programming, those libraries might not actually be possible to write. You will either end up with a more dynamic interface (doing meta-stuff at runtime), or a clunkier and more verbose interface. I think being able to expand a macro invocation to see what it turns into is enough for all but the hairiest of macros.
- flavio81 6y ago
  > It should be possible for tooling to just show you the expansion of any given macro invocation. In fact, when I used Clojure a decade ago, there was an Emacs command that would expand the macro invocation under your cursor, so you could see what code was actually being generated. Exactly. On common lisp, for example, it's just a keypress, and it has a "macro stepper" so it shows the first expansion possible, then the second expansion, and so on and so on... until you end up with compiler primitives!

wtetzner 6y ago

> I'm mostly arguing against extensive use of meta programming, which is promoted as one of the main reasons to view data as code, as meta programming is inherently disadvantaged for automated tooling. Which is weird, because in most Lisps meta programming happens at compile time. It should be possible for tooling to just show you the expansion of any given macro invocation. In fact, when I used Clojure a decade ago, there was an Emacs command that would expand the macro invocation under your cursor, so you could see what code was actually being generated. So I don't really think that's a fundamental limitation. I suspect it's more related to the fact that Lisps aren't especially popular, and don't get the attention from tooling that other languages do. > Codifying the features the meta programming supplies in the language itself or in well supported libraries But without the meta programming, those libraries might not actually be possible to write. You will either end up with a more dynamic interface (doing meta-stuff at runtime), or a clunkier and more verbose interface. I think being able to expand a macro invocation to see what it turns into is enough for all but the hairiest of macros.

flavio81 6y ago
> It should be possible for tooling to just show you the expansion of any given macro invocation. In fact, when I used Clojure a decade ago, there was an Emacs command that would expand the macro invocation under your cursor, so you could see what code was actually being generated. Exactly. On common lisp, for example, it's just a keypress, and it has a "macro stepper" so it shows the first expansion possible, then the second expansion, and so on and so on... until you end up with compiler primitives!