Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Common Lisp Object System (CLOS)

hescaide.me

Post reply on HN
Print view View original

41–50 of 90 posts

Re: Common Lisp Object System (CLOS)

#41

Post by headhasthoughts »

creepycrawler wrote: post #37
zasdffaa wrote: post #31

Earlier quoted context omitted.

This "afterthought ... poorly bolted ... worse than its predecessor" is a type of HN comment that's too common. Not being a CLOS or Lisp user, I have no idea why you say this and can learn nothing from it. HN's really starting to put me off with suchlike rife blanket-damning posts that are uninformative and usually come from people who have little experience.

Indeed, this type of threads always remind me that HN is not the same as it used to be. If you wish to learn about something (including about its worth), it's not the right place. Read books; read and write code; form your own opinions.

Your account is 52 days old, which I will admit is a poor way to estimate how long someone's been around. Look at any old thread around Arc's release and you'll see the comment quality was even lower than here.

https://news.ycombinator.com/item?id=106398

Re: Common Lisp Object System (CLOS)

#43

Post by creepycrawler »

creepycrawler wrote: post #37
zasdffaa wrote: post #31

Earlier quoted context omitted.

This "afterthought ... poorly bolted ... worse than its predecessor" is a type of HN comment that's too common. Not being a CLOS or Lisp user, I have no idea why you say this and can learn nothing from it. HN's really starting to put me off with suchlike rife blanket-damning posts that are uninformative and usually come from people who have little experience.

Indeed, this type of threads always remind me that HN is not the same as it used to be. If you wish to learn about something (including about its worth), it's not the right place. Read books; read and write code; form your own opinions.

Replying to self because HN doesn't show me reply buttons to this comment's children.

This account is 52 days old, but the user behind this has been reading and posting on HN for a bit longer (let's say since PG decided to put HN online).

For the other comment, my point is that "genuinely wise" is much rarer nowadays, and instead we're drowning in "genuinely clueless". This is why you shouldn't learn about something's worth by reading HN comments nowadays. Instead you can put a limited amount of time actually studying the subject and then decide if it's worthy of more of your time or not.

Re: Common Lisp Object System (CLOS)

#44

Post by retrocryptid »

If you like CLOS, be sure to look up "The Art of the Meta-Object Protocol." It Was written by people who were at PARC back in the day so were on the ground when Smalltalkish concepts were being developed and extended. But... it's focused on Lisp.

It describes the thinking behind an implementation of OOP for Lisp, and along the process reveals parts of the mental journey to both Smalltalk and CLOS.

https://en.m.wikipedia.org/wiki/The_Art_of_the_Metaobject_Pr...

Re: Common Lisp Object System (CLOS)

#45

Post by zasdffaa »

creepycrawler wrote: post #43
creepycrawler wrote: post #37

Earlier quoted context omitted.

Indeed, this type of threads always remind me that HN is not the same as it used to be. If you wish to learn about something (including about its worth), it's not the right place. Read books; read and write code; form your own opinions.

Replying to self because HN doesn't show me reply buttons to this comment's children. This account is 52 days old, but the user behind this has been reading and posting on HN for a bit longer (let's say since PG decided to put HN online). For the other comment, my point is that "genuinely wise" is much rarer nowadays, and instead we're drowning in "genuinely clueless". This is why you shouldn't learn about something'…

Perhaps.. but clueless comments are usually evident by the very lack of solid info. So why even post?

I get further pissed off by having people argue back when I say something from my small island of expertise (SQL and a few other things) they clearly know less than me - I can't learn from them and they won't learn from me. I don't mind n00bs, we all were once, but to willingly remain n00bs by rejecting information, well I can't comprehend it.

I miss posts from the likes of BeeOnRope. The really good people get driven away.

Re: Common Lisp Object System (CLOS)

#46

Post by jjtheblunt »

timonoko wrote: post #9

One thing bad is the word 'class'. What it is supposed to even mean? It was some fancy concept by stupid Normen when defining Simula. My Simula teacher said that you could just translate it as "design" as in "design of car and its implementation". Anyways Python's "class" is even worse: class c: a=10 print c.a c.a=13 print c.a I cannot think any English word to replace the "class". The word I am thinking of could be…

i think of "blueprint" as an analogy for what "class" is supposed to describe.

Re: Common Lisp Object System (CLOS)

#47

Post by aidenn0 »

rosebay wrote: post #10
dj_mc_merlin wrote: post #7

Meh.. I code in Common Lisp at home and Java professionally and I've never understood why people praise the CLOS so much. Like the author says, 99% of the time you don't have a reason to use OOP, and the few times you do you'd prefer to use as little as possible to keep everything sane. It's also one of the few parts of CL which are not optimized well by default, using structs or other basic data structures instead o…

Agreed. I program in CL and other languages too. I find Java developers tend to have a stronger understanding of OOP and that might be behind your insight. For all its benefits, it feels like at times many CL users miss the point of OOP. CLOS itself is great, however the decoupling of data and methods is something at times I find leads to harder to understand code.

> CLOS itself is great, however the decoupling of data and methods is something at times I find leads to harder to understand code.

I think that might be familiarity rather than anything fundamental. I often find the coupling of data and methods to lead to harder to understand code; if I want to define a new method on an object in Java, I have to either subclass it or modify the class itself. Even if the method is ancillary to the core functionality of the class. That seems strange to me.

Re: Common Lisp Object System (CLOS)

#48

Post by 0x445442 »

> Instead of instructions like in imperative programming (and modularizing it with functions), your program is a set of entities talking to each other and collectively achieving the required goal.

So it looks like the author discovered a key characteristic of OOP which many languages including Java, support.

Re: Common Lisp Object System (CLOS)

#49

Post by pfdietz »

dj_mc_merlin wrote: post #7

Meh.. I code in Common Lisp at home and Java professionally and I've never understood why people praise the CLOS so much. Like the author says, 99% of the time you don't have a reason to use OOP, and the few times you do you'd prefer to use as little as possible to keep everything sane. It's also one of the few parts of CL which are not optimized well by default, using structs or other basic data structures instead o…

CLOS is currently slower, but there are some cool ideas floating around to greatly speed it up. The roadblock has been CLOS's dynamism: everything needs to be redefinable at run time, even the classes. But it's possible for an implementation to get high efficiency even with that, using separate code snippets that are reached by a single branch (although I don't know if any CL implementation does this yet):

http://metamodular.com/SICL/call-site-optimization.pdf

(I think a modern version of Common Lisp would take this idea and run with it, making most or all built-in functions generic.)

CLOS really shines when it comes to problems that benefit from method combination, which allows one to decompose computations into reusable nuggets that can be reassembled using multiple inheritance.

Re: Common Lisp Object System (CLOS)

#50

Post by wirrbel »

jjtheblunt wrote: post #46
timonoko wrote: post #9

One thing bad is the word 'class'. What it is supposed to even mean? It was some fancy concept by stupid Normen when defining Simula. My Simula teacher said that you could just translate it as "design" as in "design of car and its implementation". Anyways Python's "class" is even worse: class c: a=10 print c.a c.a=13 print c.a I cannot think any English word to replace the "class". The word I am thinking of could be…

i think of "blueprint" as an analogy for what "class" is supposed to describe.

Earlier lisps called it „flavour“

Defflavor instead of defclass

Post reply on HN