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This further reinforces how Yegge's recent "software political axis" rant was wildly inconsistent. His characterization of Clojure was "highly conservative" based in part on the best practices avoiding macros when possible, unlike "liberal" languages including Common Lisp.

Meanwhile in his own company's coding style for Common Lisp states very similar best practices regarding macros -- they should be used "sparingly and carefully", "You must never use a macro where a function will do.", etc. The whole macros section basically reads as a list of well thought out reasons against using macros when writing code that other people will have to maintain.

Yegge: "I trust that if you know anything about Lisp, your blood is basically boiling at this point." Really? Well then maybe the google CL team doesn't know lisp or otherwise are looking for novel ways to escalate their collective blood pressure.

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Disagree, this advice regarding macros is mainstream Common Lisp thought. It's certainly been repeated enough on #lisp.

And, ah, the google CL team is, AFAIK, the former ITA, which was one of the top known Lisp shops worldwide. They know their Lisp.

No, Steve's rant was also about how Google is very much on the "Conservative" end of the political spectrum. When a conservative company uses an - as per steve's article - liberal language, you can't expect them to use it in a liberal way. The story checks out.

I disagree. The Common Lisp community commonly has had the advice to be sparing with macros. Dan Weinreb (of ITA and the Common Lisp standard) mentioned this about ITA pre-Google. Paraphrasing from memory, "You can use functions anytime. With macros you need justification. With reader macros, you need a LOT of justification."

The conventional advice is not to go nuts with macros. In normal Common Lisp code, you don't need to write many macros. And when you do, they're typically with- macros.

Now, you can be a heavy consumer of macros. That's something else. Like using the LOOP macro all the time, for instance. The DEF... forms too. If you're building a powerful new abstraction, like OOP or the metaobject protocol, then it's great to have powers normally reserved for language designers.

Also, see Rich Hickey's points: (http://news.ycombinator.com/item?id=4366661)

> Meanwhile in his own company's coding style for Common Lisp states very similar best practices regarding macros -- they should be used "sparingly and carefully", "You must never use a macro where a function will do.", etc.

This is not arguing against macros, per se. The most powerful feature of macros is controlling how / when arguments are evaluated. So, if you don't use a macro when a function (i.e. standard arg evaluation) will do, you're not missing out on the power of macros.

Yegge is wrong about this. It is generally accepted in the Common Lisp community that you avoid macros whenever possible. Here's a quote from pg's "Beating the Averages"

"Macros are harder to write than ordinary Lisp functions, and it's considered to be bad style to use them when they're not necessary."

Link to Steve Yegge's post:

https://plus.google.com/u/0/110981030061712822816/posts/KaSK...

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