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@swannodette
swannodette / gist:3217582
Created July 31, 2012 14:52
sudoku_compact.clj
;; based on core.logic 0.8-alpha2 or core.logic master branch
(ns sudoku
(:refer-clojure :exclude [==])
(:use clojure.core.logic))
(defn get-square [rows x y]
(for [x (range x (+ x 3))
y (range y (+ y 3))]
(get-in rows [x y])))
@mikelehen
mikelehen / generate-pushid.js
Created February 11, 2015 17:34
JavaScript code for generating Firebase Push IDs
/**
* Fancy ID generator that creates 20-character string identifiers with the following properties:
*
* 1. They're based on timestamp so that they sort *after* any existing ids.
* 2. They contain 72-bits of random data after the timestamp so that IDs won't collide with other clients' IDs.
* 3. They sort *lexicographically* (so the timestamp is converted to characters that will sort properly).
* 4. They're monotonically increasing. Even if you generate more than one in the same timestamp, the
* latter ones will sort after the former ones. We do this by using the previous random bits
* but "incrementing" them by 1 (only in the case of a timestamp collision).
*/
@kconner
kconner / macOS Internals.md
Last active April 22, 2024 21:28
macOS Internals

macOS Internals

Understand your Mac and iPhone more deeply by tracing the evolution of Mac OS X from prelease to Swift. John Siracusa delivers the details.

Starting Points

How to use this gist

You've got two main options:

@jboner
jboner / latency.txt
Last active May 5, 2024 03:12
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
@veekaybee
veekaybee / normcore-llm.md
Last active May 6, 2024 01:30
Normcore LLM Reads

Anti-hype LLM reading list

Goals: Add links that are reasonable and good explanations of how stuff works. No hype and no vendor content if possible. Practical first-hand accounts of models in prod eagerly sought.

Foundational Concepts

Screenshot 2023-12-18 at 10 40 27 PM

Pre-Transformer Models