Redesigning Common Lisp

Redesigning Common Lisp

Shibuya.lisp Tech Talk #8 Eitaro Fukamachi

Thank you for coming.

I’m Eitaro Fukamachi @nitro_idiot fukamachi

(and 'web-application-developer 'common-lisper)

Others

Clojure

Perl

Emacs Lisp

JavaScript

Common Lisp

GitHub product languages

GitHub product languages

I ♥ Common Lisp

because…

Common Lisp is the most powerful, expressive and fast language ever.

Common Lisp is damn powerful

• First class functions + lexical closures

• Object system + multiple dispatch

• Metaobject protocol

Common Lisp is expressive

• Reader macros

• Macros

Common Lisp is fast

• (Optional) type declaration

• Inlining functions

• Compiler macros

• Disassembler included

• Free high-performance implementation


= GOD LANGUAGE

So, here is a question.

Is Common Lisp perfect?

Is Common Lisp successful?

Is Common Lisp attractive to young people?

……………..

“well…”

Common Lisp is not sophisticated

• too-long-wordy-name-for-common-macros

• append & nconc

• elt vs aref vs nth

• getf vs gethash

• map?? mapc?? dolist?? loop??

• Functional vs Procedual

It’s because of the origin.

8 Goals of standardising Common Lisp

Commonality

Portability

Consistency

Expressiveness

Compatibility

Efficiency

PowerStability

from Common Lisp the Language

Common Lisp is a compound of MacLISP, Zetalisp, Spice Lisp, NIL and S-1 Lisp.

Common Lisp was designed for MacLISP, Zetalisp, Spice Lisp, NIL and S-1 Lisp users, not us.

Besides, Common Lisp is old.

Common Lisp = 30 years old Ruby = 19 years old JavaScript = 19 years old Clojure = 7 years old

Common Lisp was designed for people 30 years ago.

But it doesn’t mean Common Lisp is obsolete.


Common Lisp is the best one, but I’m still not fulfilled in it.

CLtL3? Almost hopeless.

Let’s redesign Common Lisp for the 21st century by ourselves.

“Common Lisp for the 21st century”

“CL21”

What is CL21?

• (One of) the next generation of Common Lisp

• Bases on Common Lisp

• Designed for us

• Actual implementation(not only discussions)

8 Goals of standardising Common Lisp

Commonality

Portability

Consistency

Expressiveness

Compatibility

Efficiency

PowerStability

from Common Lisp the Language

4 Goals of CL21

Consistency

Compatibility

Efficiency

Expressiveness

Goal 1: Consistency

Consistency of CL21

• Naming convention

• Argument order

(reverse '(1 2 3)) (nreverse '(1 2 3)) !(append '(1 2 3) '(a b c)) (nconc '(1 2 3) '(a b c))

Consistency of CL21

Common Lisp

(reverse '(1 2 3)) (nreverse '(1 2 3)) !(append '(1 2 3) '(a b c)) (nappend '(1 2 3) '(a b c))

Consistency of CL21

CL21

(getf person :name) (gethash :name person-hash)

Consistency of CL21

Common Lisp

(getf person :name) (gethash person-hash :name)

Consistency of CL21

CL21

Goal 2: Expressiveness

Expressiveness of CL21

• Specific vs Generic

• Delete useless symbols










(ed “~/.sbclrc”)




(ed “~/.sbclrc”)

Are you crazy????

(append '(1 2 3) '(a b c)) (concatenate 'vector #(1 2 3) '()) (concatenate 'string "Hello, " name)


Common Lisp

(append '(1 2 3) '(a b c)) (append #(1 2 3) '()) (append "Hello, " name)


CL21

(mapcar #'1+ '(1 2 3)) (map 'vector #'1+ #(1 2 3))


Common Lisp

(map #'1+ '(1 2 3)) (map #'1+ #(1 2 3))


CL21

(format nil "Hello, World!~%") (format nil "Hello, ~A~%" name)


Common Lisp

"Hello, World!\n" #"Hello, ${name}\n"


CL21

(parse-integer "1984") (symbol-name 'alien-technology)


Common Lisp

(coerce "1984" 'integer) (coerce 'alien-technology 'string)


CL21

(ql:quickload :cl-ppcre) (use-package :cl-ppcre) !(scan-to-strings "^(\\d{4})-(\\d{2})-(\\d{2})$" "2014-01-23") (regex-replace-all "a" "Eitaro Fukamachi" "α" :preserve-case nil)


Common Lisp

(use-package :cl21.re) !(#/^(\d{4})-(\d{2})-(\d{2})$/ "2014-01-23") (re-replace #/a/ig "Eitaro Fukamachi" "α")


CL21



CL21!! #/^(\d{4})-(\d{2})-(\d{2})$/ #/a/ig



CL21!! #/^(\d{4})-(\d{2})-(\d{2})$/ #/a/ig

Appliable Regex literal

(ql:quickload :clazy) (use-package :clazy) !(defun fib-seq () (labels ((rec (a b) (clazy:lazily (cons a (rec b (+ a b)))))) (rec 0 1))) !(head (tail (tail (tail (fib-seq))))) (lazy-seq:take 5 (fib-seq))


Common Lisp

(use-package :cl21.lazy) !(defun fib-seq () (labels ((rec (a b) (lazy-sequence (cons a (rec b (+ a b)))))) (rec 0 1))) !(first (rest (rest (rest (fib-seq))))) (elt (fib-seq) 3) (subseq (fib-seq) 0 5)


CL21



CL21!!!! lazy-sequence !!

Abstract sequence



CL21!!!! lazy-sequence !!! first rest rest rest elt subseq

Abstract sequence

Builtin sequence functions are available

Goal 3: Compatibility

Compatibility of CL21

• Written in Common Lisp

• 100% compatible with Common Lisp

• All CL libraries are available


(defsystem my-cl21-app :defsystem-depends-on (:cl21) :class :cl21-system :components ((:file "src/myapp")))


(defsystem my-cl21-app :defsystem-depends-on (:cl21) :class :cl21-system :components ((:file "src/myapp")))

! :defsystem-depends-on (:cl21) :class :cl21-system

Goal 4: Efficiency

Efficiency of CL21

• (less important in CL21, though)

• Generic methods are slow

• Compiler macros

4 Goals of CL21

Consistency

Compatibility

Efficiency

Expressiveness

Other topics: “syntax”

“syntax”

• CL21 has “syntax”

• “syntax” = readtable bound to a package

“syntax”(defsyntax cl21.process ((#\# #\`) #'run-process-reader)) !(export-syntax 'cl21.process)

(use-package :cl21.process) !#`ls -l /Users`

Other topics: Standard libraries

Batteries included (?)

• cl21.re

• cl21.process

• cl21.lazy

• cl21.os

Remember CL21 is 100% compatible with Common Lisp

You see how Common Lisp is expressive and growable?

Current status

Current status

• Still in development

• No backward-compatibility guaranteed

• We’ll release in the 21st century

• Not settled discussions

• loop vs iterate vs series

WEB SITE:

cl21.org !

GITHUB:

github.com/cl21/cl21

http://cl21.org

https://github.com/cl21/cl21

Make Lisp the Premier Prototyping Language.

— Richard P. Gabriel “Worse Is Better”

http://www.dreamsongs.com/WIB.html

Thanks.

EITARO FUKAMACHI 8arrow.org @nitro_idiot fukamachi

http://8arrow.org

Technology

Redesigning Common Lisp