ciel/FAQ.org

* About CIEL

** Is CIEL yet another language re-design?

Absolutely not. CIEL is plain Common Lisp. We don't redefine the
semantics of the language. CIEL is a collection of useful libraries,
shipped as one Quicklisp meta-library, a core image and an executable.


** Is CIEL a standard library?

No, we can't say that. We ship useful libraries written by a variety of
people, including ourselves, and we make them available to you so you
don't have to spend time looking for them, choosing them, installing
them and importing them. We use the same libraries that every other
lisper can find on Quicklisp. We provide a core image and a
ready-to-use REPL to make on-boarding even easier.

** If I use CIEL, do I learn Common Lisp?

Yes you do. And in addition you'll be acquainted to useful and often
popular third-party libraries and utilities. They are all referenced
on our website.

** How do I switch from CIEL to plain Common Lisp?

You will have to know what external libraries you are using. Mainly,
by reading CIEL's documentation, or by using your editor's "go to
definition" feature (=M-.= in Slime) to find out. You'll have to use
the =cl= or =cl-user= package instead of =ciel-user=, and you'll have
to declare your dependencies yourself in your project's =.asd=
file.

Eventually, there could be a script that does that for you.

** Is CIEL as fast as Common Lisp?

In general, yes. Only some functions are more generic, thus slower, than
default Common Lisp. For example, =access=. That is more the case if you
use =generic-ciel=.

** Is CIEL stable?

No. At least not in the Common Lisp sense of stability, which means
"very stable". CIEL is as stable as the set of the libraries it
includes. We have solutions to improve stability, so this is an open
question (using our own Quicklisp distribution, redifining a symbol in
case of an upstream change for backwards compatibility,…).

Generally though, the ecosystem is quite conservative. We saw
deprecation warnings staying for 12 years.

** Who is CIEL for?

CIEL is for everybody who wants to discover Common Lisp, or for more
experienced lispers who want to have a batteries-included Common Lisp
distribution at hand.

** I am a seasoned lisper, why should I care?

You must regularly hear that "getting started with Common Lisp is hard",
"Common Lisp is full of quirks", "finding what one needs is
difficult", etc. CIEL is an attempt to ease on-boarding, and getting rid
off these (legitimate) complaints.

You can test and discover new libraries.

You can show CIEL to your non-lispers friends and colleagues, without
saying embarrassing things like: "Just install rlwrap". "To join
strings, use format's ~{ @ : }". "Yeah, there's parse-integer but not
parse-float, just install it". "To see what's in a hash-table, I'll
give you a snippet". etc.

** What is CIEL for?

Please see the project's homepage, and write to us if it is not clear enough!

* About Common Lisp

** What is Common Lisp good for, really?

We have a famous quote for this question:

#+begin_quote
Please don't assume Lisp is only useful for Animation and Graphics,
AI, Bioinformatics, B2B and Ecommerce, Data Mining, EDA/Semiconductor
applications, Expert Systems, Finance, Intelligent Agents, Knowledge
Management, Mechanical CAD, Modeling and Simulation, Natural Language,
Optimization, Research, Risk Analysis, Scheduling, Telecom, and Web
Authoring just because these are the only things they happened to
list.

  Kent Pitman
#+end_quote

** Will I get hit by the Lisp curse?

The very serious Lisp curse is that once you taste Lisp, all other
languages become insipid. CIEL brings you higher in the sky, at a
higher risk. Sorry!