ashok-khanna

(defun make-url-part (title)
  "Generate a url-part from a title. A url-part should only have alphanumeric characters or dashes (in place of spaces)."
  (string-downcase
   (delete-if #'(lambda (x) (not (or (alphanumericp x) (char= #\- x))))
              (substitute #\- #\Space title))))

ashok-khanna

(ql:quickload '("clack" "lack" "lack-middleware-mount" "cl-dotenv" "quri" "uuid" "dexador" "jsown"))

(defpackage #:example
  (:use #:common-lisp))

(in-package #:example)

(.env:load-env (merge-pathnames ".env"))

(defvar *okta-authorize-uri* (quri:uri (uiop:getenv "OKTA_AUTHORIZE_URI")))

ashok-khanna

Reader Macros in Common Lisp

This post also appears on lisper.in.

Reader macros are perhaps not as famous as ordinary macros. While macros are a great way to create your own DSL, reader macros provide even greater flexibility by allowing you to create entirely new syntax on top of Lisp.

Paul Graham explains them very well in [On Lisp][] (Chapter 17, Read-Macros):

The three big moments in a Lisp expression's life are read-time, compile-time, and runtime. Functions are in control at runtime. Macros give us a chance to perform transformations on programs at compile-time. ...read-macros... do their work at read-time.

ashok-khanna

CL-USER> (values call-arguments-limit lambda-parameters-limit multiple-values-limit (lisp-implementation-type))
4611686018427387903 (62 bits, #x3FFFFFFFFFFFFFFF)
4611686018427387903 (62 bits, #x3FFFFFFFFFFFFFFF)
4611686018427387903 (62 bits, #x3FFFFFFFFFFFFFFF)
"SBCL"

CL-USER> (values call-arguments-limit lambda-parameters-limit multiple-values-limit (lisp-implementation-type))
65536
4096
200

ashok-khanna

cd cm co cp cq cr cs cu cv cx cy cz

dc dm dq dr ds du dv dx dy dz

gb gc gl gs gy

vc vd vm vo vp vq vr vs vu vv vx vy vz

yc yd ym yo yp yq yr ys yu yv yx yz

ashok-khanna

From welch@thor.oar.net Thu Oct 20 16:53:41 EDT 1994
Article: 15160 of comp.lang.lisp
Path: cantaloupe.srv.cs.cmu.edu!das-news2.harvard.edu!news2.near.net!news.mathworks.com!usenet.eel.ufl.edu!usenet.cis.ufl.edu!caen!math.ohio-state.edu!magnus.acs.ohio-state.edu!usenet.ins.cwru.edu!ns.mcs.kent.edu!kira.cc.uakron.edu!malgudi.oar.net!malgudi.oar.net!welch
From: welch@thor.oar.net (Arun Welch)
Newsgroups: comp.lang.lisp
Subject: CL History (was Re: Why do people like C?)
Date: 20 Oct 94 15:34:10
Organization: OARnet
Lines: 3244
Message-ID: <WELCH.94Oct20153410@thor.oar.net>

ashok-khanna

;; Suppose we have a collection of N documents.
;; Define Fij to be the frequency of term i in document j.
;; Define TFij to be Fij/max(k,Fkj),
;;   that is, the term frequency of term i in document j is Fij
;;   normalized by dividing it by the maximum number of occurrences
;;   of any term in the same document.
;; Define IDFi to be log2(N/ni).
;; The TF.IDF score for term i in document j is then defined to be
;; TFij x IDFi.  The terms with the highest TF.IDF score are often
;; the terms that best characterize the topic of the document.

ashok-khanna

Courtesy of ignis volens on SO: https://stackoverflow.com/questions/69675964/how-to-get-the-filename-where-a-function-is-defined-in-common-lisp/69677540#69677540

If what you seek is a portable solution – one that is written in portable CL – then the answer to that is to define wrappers for defining forms and then use the wrappers.

(defvar *flocs* (make-hash-table :test #'equal))

(defgeneric function-location (f/name)
  (:method ((name t))

ashok-khanna

Context from IRC logs for future reference.

[12:36]  <kushal> nikodemus, can you point me to some tutorial on debugging on sbcl ?
[12:37]  * andreer (andreer@flode.pvv.ntnu.no) has joined #quicklisp
[12:38]  <nikodemus> kushal: no really good ones actually exist at the moment. i'm planning on writing one before the year is out, but... in the meanwhile, i can give some pointers
[12:38]  <nikodemus> a couple of questions: is this a general question, or do you have a specific issue you need to debug?
[12:39]  <kushal> right now , general, managed to debug the specific issue somehow :)
[12:39]  <nikodemus> ok. are you using slime?
[12:39]  <kushal> nikodemus, yes and no both
[12:40]  <nikodemus> good. :)

ashok-khanna

;;;;****************************************************************************

;;;; SPECIALIZING SLOTS WITH THE DEFINE-CLASS MACRO

;;;;****************************************************************************

;;;;***** RATIONALE ************************************************************

;;; In this file, we introduce a DEFINE-CLASS macro that proposes a particular
;;; approach to defining CLOS classes such that type information is retained