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@vishnuvyas
vishnuvyas / levenshtein.clj
Created May 6, 2011 05:29
A purely functional implementation of levenshtein distance in clojure
(ns levenshtein
^{:doc "A purely functional implementation of the levenshtien distance in clojure"})
(defn- compute-next-row
"computes the next row using the prev-row current-element and the other seq"
[prev-row current-element other-seq pred]
(reduce
(fn [row [diagonal above other-element]]
(let [update-val
(if (pred other-element current-element)
@nifl
nifl / grok_vi.mdown
Created August 29, 2011 17:23
Your problem with Vim is that you don't grok vi.

Answer by Jim Dennis on Stack Overflow question http://stackoverflow.com/questions/1218390/what-is-your-most-productive-shortcut-with-vim/1220118#1220118

Your problem with Vim is that you don't grok vi.

You mention cutting with yy and complain that you almost never want to cut whole lines. In fact programmers, editing source code, very often want to work on whole lines, ranges of lines and blocks of code. However, yy is only one of many way to yank text into the anonymous copy buffer (or "register" as it's called in vi).

The "Zen" of vi is that you're speaking a language. The initial y is a verb. The statement yy is a simple statement which is, essentially, an abbreviation for 0 y$:

0 go to the beginning of this line. y yank from here (up to where?)

@domenic
domenic / portable-node.md
Created May 25, 2012 21:03
Tips for Writing Portable Node.js Code

Node.js core does its best to treat every platform equally. Even if most Node developers use OS X day to day, some use Windows, and most everyone deploys to Linux or Solaris. So it's important to keep your code portable between platforms, whether you're writing a library or an application.

Predictably, most cross-platform issues come from Windows. Things just work differently there! But if you're careful, and follow some simple best practices, your code can run just as well on Windows systems.

Paths and URLs

On Windows, paths are constructed with backslashes instead of forward slashes. So if you do your directory manipulation

@jboner
jboner / latency.txt
Last active June 29, 2024 19:54
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@rgreenjr
rgreenjr / postgres_queries_and_commands.sql
Last active June 28, 2024 08:56
Useful PostgreSQL Queries and Commands
-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
FROM pg_stat_activity
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc;
-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'
@zspecza
zspecza / stylus-best-practices.md
Last active May 27, 2021 05:25
Stylus Best Practices

Stylus Best Practices

Introduction

This is a curated set of conventions and best practices for Stylus, an expressive, dynamic, robust and advanced CSS preprocessor. Frustrated with there not being a set of conventions set in place (that could be easily found), I set forth to find out on my own.

@mziwisky
mziwisky / Oauth2.md
Last active February 15, 2024 23:31
Oauth2 Explanation

OAUTH2

The Problem

I’m a web app that wants to allow other web apps access to my users’ information, but I want to ensure that the user says it’s ok.

The Solution

I can’t trust the other web apps, so I must interact with my users directly. I’ll let them know that the other app is trying to get their info, and ask whether they want to grant that permission. Oauth defines a way to initiate that permission verification from the other app’s site so that the user experience is smooth. If the user grants permission, I issue an AuthToken to the other app which it can use to make requests for that user's info.

Note on encryption

Oauth2 has nothing to do with encryption -- it relies upon SSL to keep things (like the client app’s shared_secret) secure.

@jashkenas
jashkenas / semantic-pedantic.md
Last active June 27, 2024 19:00
Why Semantic Versioning Isn't

Spurred by recent events (https://news.ycombinator.com/item?id=8244700), this is a quick set of jotted-down thoughts about the state of "Semantic" Versioning, and why we should be fighting the good fight against it.

For a long time in the history of software, version numbers indicated the relative progress and change in a given piece of software. A major release (1.x.x) was major, a minor release (x.1.x) was minor, and a patch release was just a small patch. You could evaluate a given piece of software by name + version, and get a feeling for how far away version 2.0.1 was from version 2.8.0.

But Semantic Versioning (henceforth, SemVer), as specified at http://semver.org/, changes this to prioritize a mechanistic understanding of a codebase over a human one. Any "breaking" change to the software must be accompanied with a new major version number. It's alright for robots, but bad for us.

SemVer tries to compress a huge amount of information — the nature of the change, the percentage of users that wil

@prakhar1989
prakhar1989 / richhickey.md
Last active November 8, 2023 17:19 — forked from stijlist/gist:bb932fb93e22fe6260b2
richhickey.md

Rich Hickey on becoming a better developer

Rich Hickey • 3 years ago

Sorry, I have to disagree with the entire premise here.

A wide variety of experiences might lead to well-roundedness, but not to greatness, nor even goodness. By constantly switching from one thing to another you are always reaching above your comfort zone, yes, but doing so by resetting your skill and knowledge level to zero.

Mastery comes from a combination of at least several of the following:

@unbracketed
unbracketed / branch-fu.md
Created April 7, 2015 17:49
Moving commits between branches

Example: Moving up to a few commits to another branch

Branch A has commits (X,Y) that also need to be in Branch B. The cherry-pick operations should be done in the same chronological order that the commits appear in Branch A.

cherry-pick does support a range of commits, but if you have merge commits in that range, it gets really complicated

git checkout branch-B
git cherry-pick X
git cherry-pick Y