CAR and CDR

[RBerenguel]

I always forgot which was which until I actually forced me to use them for a while (and "while" was too long). The only cool thing of the names is that you can get a cryptic sticker "My other car is a cdr" that no-one will understand but will make you jiggle each morning

[phoboslab]

I feel the same way about many *nix commands. A while ago I thought it was neat to have TLAs[1] for everything, but now I just think it's bad "API" design.

Why is it ls instead of list? chmod instead of permissions? grep instead of search? mv, cp, rm instead of move, copy, remove? Is it really so much work to type a few more characters to justify this?

Programming langue APIs (or rather their libraries) have come a long way since the C days in that regard, but OS wise we're still stuck with these cryptic names.

[1] http://en.wikipedia.org/wiki/Three-letter_acronym

[petercooper]

Mine is "car" and "CarDriveR" (implying first comes the car, then its driver). "CorriDoR" is another one which implies the extra length a bit better.

[csmuk]

Still prefer first and rest. At least that has meaning outside the first use of car and cdr.

[agumonkey]

I can't disagree with that, but after learning clojure I realized that I interned `car` and `cdr` as symbols of which I like :

  - the symmetry: 'c[ad]r'
  - thus same size
  - small size (3)

and ended up being annoyed by `first` and `rest`. I see them as APL-like characters now.

ps: based on that, head/tail, hd/tl, fst/snd (seen in ml dialects) are also good candidates.

[mercurial]

I'll take head/tail over first/rest, but first/rest is not too bad.

[mrottenkolber]

It has nothing to do with preference. FIRST and REST are to be used when working on a LIST, CAR and CDR when working on CONS cells.

[yati]

Same here, but cons cells can be used to model things other than lists, where semantically first and rest don't make sense.

[outworlder]

They are better, until you try to compose them :)

[xmonkee]

but saying "cudder" is so much more fun

[elrzn]

It's a pity they're not standard in many other languages. I'm not a fan of having to type first/rest or playing around with syntax soup and I really miss caddadadaddaaaaaring around.

sub car { $_[0] } sub cdr { shift; @_ } # every utils module ever

[draegtun]

Plonk that into an autobox module (like perl5i and/or autobox::Core) and enjoying even more caddadadaddaaaaaring around!

For eg:

  use perl5i::2;

  sub autobox::Core::ARRAY::car { $_[0]->[0] }

  sub autobox::Core::ARRAY::cdr {
      my $last = $#{$_[0]};
      wantarray ? @{$_[0]}[1 .. $last] : [@{$_[0]}[1 .. $last]];
  }

then...

  my @a = 1..4;

  @a->car;             # 1
  @a->cdr->cdr->car;   # 3
  @a->cdr;             # 2, 3, 4

  my @x = @a->cdr;
  @x->cdr;             # 3, 4

Some refs: https://metacpan.org/pod/perl5i | https://metacpan.org/pod/autobox::Core

[csmuk]

Noooooooooooooooooooooooooooooooooooooooo.

Perl can be written ugly enough without introducing car and cdr to it!

[joeygibson]

I first learned Lisp so long ago that car and cdr are still ingrained in my head. first and last feel somehow wrong, to me.

[kang]

quote used to mark data as opposed to code can be tricky while using CDR & CAR : http://stackoverflow.com/questions/18697105/cdadr-on-nested-...

[Syssiphus]

:* <3 u LISP

[derleth]

I like them because they don't guide thought: They're abstract names for abstract concepts. They don't impose any interpretation on the ideas, they simply present them for what they are. Having to break down a less-useful conceptual model is even more difficult than building a more-useful one.