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@dacr
dacr / index.md
Last active May 25, 2024 10:21
David's programming examples knowledge base / published by https://github.com/dacr/code-examples-manager #fecafeca-feca-feca-feca-fecafecafeca/b4d6e899f31bef6ed55c732edc59ad88d088edae

David's programming examples knowledge base

akka-pekko

@yidas
yidas / csr.conf.md
Last active May 22, 2024 12:11
Certificate(CSR) configuration file

Openssl commands:

openssl genrsa -out self-ssl.key
openssl req -new -key self-ssl.key -out self-ssl.csr -config csr.conf
openssl x509 -req -days 365 -in self-ssl.csr -signkey self-ssl.key -out self-ssl.crt -extensions req_ext -extfile csr.conf

Sign from Root CA: openssl x509 -req -days 365 -extensions req_ext -extfile csr.conf -CA RootCA.crt -CAkey RootCA.key -in self-ssl.csr -out self-ssl.crt

@jonhoo
jonhoo / cell-tests.rs
Last active May 13, 2024 09:58
cell-refcell-rc
// these aren't _quite_ functional tests,
// and should all be compile_fail,
// but may be illustrative
#[test]
fn concurrent_set() {
use std::sync::Arc;
let x = Arc::new(Cell::new(42));
let x1 = Arc::clone(&x);
std::thread::spawn(move || {
@debasishg
debasishg / gist:8172796
Last active May 10, 2024 13:37
A collection of links for streaming algorithms and data structures

General Background and Overview

  1. Probabilistic Data Structures for Web Analytics and Data Mining : A great overview of the space of probabilistic data structures and how they are used in approximation algorithm implementation.
  2. Models and Issues in Data Stream Systems
  3. Philippe Flajolet’s contribution to streaming algorithms : A presentation by Jérémie Lumbroso that visits some of the hostorical perspectives and how it all began with Flajolet
  4. Approximate Frequency Counts over Data Streams by Gurmeet Singh Manku & Rajeev Motwani : One of the early papers on the subject.
  5. [Methods for Finding Frequent Items in Data Streams](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.187.9800&rep=rep1&t

Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x
@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = git@github.com:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

#![warn(rust_2018_idioms)]
#[derive(Debug)]
pub struct StrSplit<'haystack, D> {
remainder: Option<&'haystack str>,
delimiter: D,
}
impl<'haystack, D> StrSplit<'haystack, D> {
pub fn new(haystack: &'haystack str, delimiter: D) -> Self {
@Icelandjack
Icelandjack / Yoneda_II.markdown
Last active April 8, 2024 11:08
Yoneda Intuition from Humble Beginnings

(previous Yoneda blog) (reddit) (twitter)

Yoneda Intuition from Humble Beginnings

Let's explore the Yoneda lemma. You don't need to be an advanced Haskeller to understand this. In fact I claim you will understand the first section fine if you're comfortable with map/fmap and id.

I am not out to motivate it, but we will explore Yoneda at the level of terms and at the level of types.

@quelgar
quelgar / typed_errors.md
Last active January 16, 2024 09:36
Every Argument for Static Typing Applies to Typed Errors

Every Argument for Static Typing Applies to Typed Errors

Think of all the arguments you've heard as to why static typing is desirable — every single one of those arguments applies equally well to using types to represent error conditions.

An odd thing I’ve observed about the Scala community is how many of its members believe that a) a language with a sophisticated static type system is very valuable; and b) that using types for error handling is basically a waste of time. If static types are useful—and if you like Scala, presumably you think they are—then using them to represent error conditions is also useful.

Here's a little secret of functional programming: errors aren't some special thing that operate under a different set of rules to everything else. Yes, there are a set of common patterns we group under the loose heading "error handling", but fundamentally we're just dealing with more values. Values that can have types associated with them. There's absolutely no reason why the benefits of static ty