Gih's Blog

Thrush calls in Common Lisp

Implement the "->" operator of Clojure: http://clojuredocs.org/clojure_core/clojure.core/-%3E in CL, that's funny.

->

Threads the expr through the forms. Inserts x as the second item in the first form, making a list of it if it is not a list already. If there are more forms, inserts the first form as the second item in second form, etc.

(defmacro -> (x &optional (form nil form-supplied-p) &rest more)
  (if form-supplied-p
      (if more
          `(-> (-> ,x ,form) ,@more)
          (if (listp form)
              `(,(car form) ,x ,@(cdr form))
              (list form x)))
      x))

How does it works?

CL-USER> (-> 1
             (+ 1)
             (+ 2)
             (+ 3))

7
CL-USER> 

=== (+ (+ (+ 1 1) 2) 3)

See another example:

CL-USER> (-> 10
             (- 5)
             (- 5)
             (- 5))
-5
CL-USER> 

=== (- (- (- 10 5) 5) 5)

How if I want (- 5 (- 5 (- 5 10)))?

There is ->> to do this. http://clojuredocs.org/clojure_core/clojure.core/-%3E%3E

->>

Threads the expr through the forms. Inserts x as the last item in the first form, making a list of it if it is not a list already. If there are more forms, inserts the first form as the last item in second form, etc.

(defmacro ->> (x &optional (form nil form-supplied-p) &rest more)
  (if form-supplied-p
      (if more
          `(->> (->> ,x ,form) ,@more)
          (if (listp form)
              `(,(car form) ,@(cdr form) ,x)
              (list form x)))
      x))

This one looks more useful sometimes.

CL-USER> (->> (list 1 2 3 4 5)
              (reduce '+)
              (* 2)
              (- 5))
-25
CL-USER> 

=== (- 5 (* 2 (reduce '+ '(1 2 3 4 5))))

Secure your cookies of Hunchentoot in Common Lisp.

Encrypt and decrypt cookies in hunchentoot. What is COOKIE?

Hunchentoot - The Common Lisp web server formerly known as TBNL

Hunchentoot is a web server written in Common Lisp and at the same time a toolkit for building dynamic websites. As a stand-alone web server, Hunchentoot is capable of HTTP/1.1 chunking (both directions), persistent connections (keep-alive), and SSL.

By default, hunchentoot supports cookies, but all cookies will be exposed once a request was done from the client. And there is not a solution to secure the cookies transform by now in hunchentoot. So the temporary choice is using the hunchentoot session:

Read more »

这么玩 lisp，实在让人蛋疼！

取个环境变量都要这么折腾：

(defun getenv (var)
  #+cmu (cdr (assoc (if (symbolp var)
                        var
                        (intern var :keyword))
                    ext:*environment-list*))
  #+sbcl (sb-ext:posix-getenv (string var))
  #+lispworks (hcl:getenv var)
  #+clisp (ext:getenv (string var))
  #+allegro (sys:getenv (string var))
  #-(or cmu sbcl lispworks clisp allegro)
  (error "GETENV not implemented for your Lisp platform."))

To clean up old packages in quicklisp

(map nil 'ql-dist:clean (ql-dist:all-dists))

A nice ORM library in common lisp

Crane project home page: http://eudoxia0.github.io/crane/

(filter 'user) ;; Returns everything

(filter 'user :name "Eudoxia")(filter 'user (:> :age 21))

;; Returns a single object
(single 'user :name "Eudoxia");;Throws an error ifthis returns more
;; than one object(single!'user (:< age 35))

;; t if a match exists, nil otherwise
(exists 'user :name "Eudoxia");;Ifthis record doesn't exist create it
(get-or-create 'user :name "Eudoxia":age 19)

cl-common-blog博客功能基本完善

划了个 0.2 版本, 个人测试, 已经相当稳定了, 而且比现在的博客方便, 再过不久我就完全使用cl-common-blog. 博客地址改为 http://blog.gihnius.net/.
写一个博客太简单了, 很多lisp的特性/功能都没有用到, 可能还不如写一个emacs插件折腾人. 当然, 这么说也是基于自己对博客应用的定义, 如果想的复杂, 就可以做得非常复杂, 可是没用. 接下来, 我计划使用common lisp开发一些应用. Planing...

用Common Lisp写的博客程序可用了!

发布了源代码, 并部署到 dev.gihnius.net .

功能很普通, 只能算一个可运行的程序. 毕竟是第一次试手 lisp 的 web 应用.

一个人工智能聊天机器人

Alan

听说是 lisp 写的.比较有趣, 有空不妨跟它聊几句!