chaitanyagupta

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.

h4cc

#
# Ubuntu 14.04 LTS (Trusty Tahr)
#
# Basic packages i usually install
#
# Author: Julius Beckmann <[email protected]>
#
# For 16.04 Xenial Xerus: https://gist.github.com/h4cc/fe48ed9d85bfff3008704919062f5c9b
#

masatoi

(ql:quickload 'lispbuilder-sdl)
(ql:quickload 'lispbuilder-sdl-gfx)
(ql:quickload 'alexandria)
 
(defparameter world (make-array '(100 100) :element-type 'fixnum))
 
;; initialize
(defun init-world! (world)
  (loop for i from 0 to (1- (array-dimension world 0)) do
    (loop for j from 0 to (1- (array-dimension world 1)) do

john2x

Clojure Destructuring Tutorial and Cheat Sheet

(Related blog post)

Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.

Vectors and Sequences

shortsightedsid

; Short guide to TCP/IP Client/Server programming in Common Lisp using usockets
;
; The main reason for this guide is because there are very few examples that
; explain how to get started with socket programming with Common Lisp that I
; could understand. After spending a day trying, I finally came up with a small
; bit of code that makes it easy to understand the basics. I've written this
; primarily for myself, but should help others get started as well.

; As usual, we will use quicklisp to load usocket.

chomy

(defpackage :BCM2835 
	(:use :FFI)
	(:export :init
		:close
		:gpio-fsel
		:gpio-write
		:gpio-lev
		:gpio-set
		:gpio-clr
		:delay

pedropazello

Haskell: Primeiros passos e bookmarks.

Primeiros passos:

• Getting started with Haskell
• Learn Haskell

Livros:

• Learn You a Haskell for Great Good!
• Real World Haskell
• Free programming books: Haskell

cstrelioff

process corpus for lda

In a blog post I wrote about the python package lda, see here, I used the pre-processed data (included with the lda package) for the example. I have since received many questions regarding the document-term matrix, the titles, and the vocabulary-- where do they come from? This gist will use the textmining package to (hopefully) help answer these types of questions.

526avijitgupta

emacs --daemon to run in the background. emacsclient.emacs24 <filename/dirname> to open in terminal

NOTE: "M-m and SPC can be used interchangeably".

• Undo - C-/
• Redo - C-?
• Change case: 1. Camel Case : M-c 2. Upper Case : M-u

3. Lower Case : M-l

onlurking

import argparse
import urllib.request
import os
import img2pdf

from os import walk
from os.path import join
from bs4 import BeautifulSoup

work_dir = os.path.dirname(__file__)