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Comment by yonaguska | Hacker News Reader

I've been meaning to read this for quite some time, but I've been told that the idioms and coding style is outdated, or not very good. This isn't going to stop me, but I'd like to know from some experienced lispers what problems I might encounter. Especially as I'm pretty inexperienced myself. I definitely won't know what to look for.

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It is written to a prior version of the Common Lisp standard, and with a very old-fashioned style. You'll see calls like (REPLACA pair val) instead of (SETF (CAR pair) val) and so on. That will irk you if you are a Common Lisp hacker already. If you're not, just keep in mind that good CL style results in somewhat prettier code than that in On Lisp.

I tried reading this back when I started writing lisp- and it's been a year since. I know I got stuck when I couldn't find functions in slime with C-d C-h, and just assumed that they were defined by the book. This is much more reassuring.

REPLACA and its cousin REPLACD are part of the Common Lisp standard, but they are indeed something you should probably never see. Even for mapping across a structure or something I'd prefer to write my own inline function. They along with TERPRI (newline) are the ugliest function names of CL.

The book still works even if you assume every specific line of lisp in it is hopelessly outdated (I wouldn't know, I'm not a lisp programmer).

Suppose you were looking at lisps and got around to the part where you realize homiconicity makes it possible (and/or sensible) to have language facilities like syntax macros. What would such a facility look like in practice? What would it be used for and how? What could go wrong defining it or using it? That's the sort of thing that's covered in On Lisp and it makes it an interesting read for any sort of programmer, rather than just a lisp one. The book is short, without being incomprehensibly dense, you get easily get a feel for it from just browsing the PDF for a bit. And the concepts being presented are a lot easier to digest than, say, 'what if your language was really good at category theory'.

The book uses common lisp, so you'll need to know how to read that. Otherwise I think you should be fine. It's not a book about idioms or coding styles, but about thinking in lisp. If the code examples are confusing, it'll be because you're not sure what something means in common lisp or because you're learning new ideas, not because the code is poorly written. So, if you treat it as a book of ideas as opposed to "teach yourself x language in 24 hours", you should be OK :)

However, if you ARE looking for a "teach yourself Lisp in 24 hours" type of book, you could do a lot worse than "Practical Common Lisp" by Peter Seibel (http://www.amazon.com/Practical-Common-Lisp-Peter-Seibel/dp/...).

PCL is also available for free at http://www.gigamonkeys.com/book/

Another rec: Land of Lisp - http://landoflisp.com/ - is also very good if you're looking to get up to speed with the absolute bare bones, so to speak, fairly quickly.

I love the comic: http://landoflisp.com/#guilds

I'm not an experienced lisper, but onlisp lacks what sicp describe when talking about abstraction barriers/layers. Also too much mutation. There's good content (macro, logic programming, patterns) but you need to detach from low-level lisp hackery.

Tain't Scheme---err Racket, 'tis Common Lisp, warts and all...

From a clojure perspective it is somewhat true. The clojure community tried to avoid macros as much as possible and doing to much with macros should be avoided.

There are of course still tons of examples in the book that are very useful for clojure as well.

I think both On Lisp and ANSI Common Lisp from PG are good books.

The only criticism I have is that PG does not write code in "Common Lisp style". It's often more of Scheme with Common Lisp.

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