jfarmer

true and false vs. "truthy" and "falsey" (or "falsy") in Ruby, Python, and JavaScript

Many programming languages, including Ruby, have native boolean (true and false) data types. In Ruby they're called true and false. In Python, for example, they're written as True and False. But oftentimes we want to use a non-boolean value (integers, strings, arrays, etc.) in a boolean context (if statement, &&, ||, etc.).

This outlines how this works in Ruby, with some basic examples from Python and JavaScript, too. The idea is much more general than any of these specific languages, though. It's really a question of how the people designing a programming language wants booleans and conditionals to work.

If you want to use or share this material, please see the license file, below.

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vincent178

SQLite3 Cheat Sheet

Info

Download from: http://www.sqlite.org/download.html Getting Started: http://www.sqlite.org/sqlite.html Documentation: http://www.sqlite.org/docs.html

sranso

notes of things i learn while watching destroy all software

##das-0001-statistics-over-git-repositories

• git rev-list HEAD -- takes the ref (in this case HEAD) and crawling backwards. so the most recent commit will appear first
  • to reverse (have most recent be first) git rev-list --reverse HEAD oldest -> newest
• xargs
  • takes multiline output and joins them with a space
  • e.g.

$ echo '1

santisbon

On Good Taste

Linus Torvalds in an interview talked about the idea of good taste in code or what I like to call elegance. As one might expect from two slides meant to make a point during a talk, he omits a lot of details to keep it short and simple. This post digs into the specifics of his example (deleting an element from a list) and adds another example (inserting an element in a list) including working code.

Example from Linus

This is an example of removing an element from a singly-linked list. It's one of the first data structures you learn about when you start learning about computer science and programming. The reason it doesn't show particularly good taste is because we have that condition at the end where we take a different action depending on whether the element we want to remove is at the beginning of the list or somewhere in the middle.

![Bad taste](http://

yegappan

Vim Script for Python Developers

This is a guide to Vim Script development for Python developers. Sample code for the various expressions, statements, functions and programming constructs is shown in both Python and Vim Script. This is not intended to be a tutorial for developing Vim scripts. It is assumed that the reader is familiar with Python programming.

For an introduction to Vim Script development, refer to usr_41.txt, eval.txt and Learn Vimscript the Hard Way

For a guide similar to this one for JavaScript developers, refer to Vim Script for the JavaScripter

This guide only describes the programming constructs that are present in both Python and Vim. The constructs that are unique to Vim (e.g. autocommands, [key-mapping](https://vimhelp.org/map.txt.html#key-m