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@j3j5
j3j5 / gist:8b3e48ccad746b90a54a
Last active August 12, 2025 13:40
Adyen Test Card Numbers
Adyen Test Card Numbers
These cards are only valid on our TEST system and they will never involve any actual transaction or transfer of funds. The TEST card numbers will not work on the Adyen LIVE Platform.
For all cards use the following expiration and CVV2/CVC2/or CID for Amex.
For all cards:
Expiration Dates CVV2 / CVC3 CID (American Express)
08/2018 OR 10/2020 737 7373
@JunichiIto
JunichiIto / alias_matchers.md
Last active September 5, 2025 14:24
List of alias matchers in RSpec 3

This list is based on aliases_spec.rb.

You can see also Module: RSpec::Matchers API.

matcher aliased to description
a_truthy_value be_truthy a truthy value
a_falsey_value be_falsey a falsey value
be_falsy be_falsey be falsy
a_falsy_value be_falsey a falsy value
@Integralist
Integralist / Ruby Lambdas.md
Last active August 28, 2025 08:25
Ruby lambdas

Lambda: standard

# Creating a lambda
l = lambda { |name| "Hi #{name}!" }

# Executing the lambda
l.call("foo") # => Hi foo!
@subudeepak
subudeepak / WebSockets.md
Last active October 24, 2025 09:19
The problems and some security implications of websockets - Cross-site WebSockets Scripting (XSWS)

WebSockets - An Introduction

WebSockets is a modern HTML5 standard which makes communication between client and server a lot more simpler than ever. We are all familiar with the technology of sockets. Sockets have been fundamental to network communication for a long time but usually the communication over the browser has been restricted. The general restrictions

  • The server used to have a permanent listener while the client (aka browser) was not designated any fixed listener for a more long term connection. Hence, every communication was restricted to the client demanding and the server responding.
  • This meant that unless the client requested for a particular resource, the server was unable to push such a resource to the client.
  • This was detrimental since the client is then forced to check with the server at regular intervals. This meant a lot of libraries focused on optimizing asynchronous calls and identifying the response of asynchronous calls. Notably t
@kevin-smets
kevin-smets / iterm2-solarized.md
Last active October 25, 2025 09:29
iTerm2 + Oh My Zsh + Solarized color scheme + Source Code Pro Powerline + Font Awesome + [Powerlevel10k] - (macOS)

Default

Default

Powerlevel10k

Powerlevel10k

@XVilka
XVilka / TrueColour.md
Last active October 9, 2025 17:55
True Colour (16 million colours) support in various terminal applications and terminals

THIS GIST WAS MOVED TO TERMSTANDARD/COLORS REPOSITORY.

PLEASE ASK YOUR QUESTIONS OR ADD ANY SUGGESTIONS AS A REPOSITORY ISSUES OR PULL REQUESTS INSTEAD!

Falsehoods programmers believe about prices

  1. You can store a price in a floating point variable.
  2. All currencies are subdivided in 1/100th units (like US dollar/cents, euro/eurocents etc.).
  3. All currencies are subdivided in decimal units (like dinar/fils)
  4. All currencies currently in circulation are subdivided in decimal units. (to exclude shillings, pennies) (counter-example: MGA)
  5. All currencies are subdivided. (counter-examples: KRW, COP, JPY... Or subdivisions can be deprecated.)
  6. Prices can't have more precision than the smaller sub-unit of the currency. (e.g. gas prices)
  7. For any currency you can have a price of 1. (ZWL)
  8. Every country has its own currency. (EUR is the best example, but also Franc CFA, etc.)
@JoshCheek
JoshCheek / void_value_expressions.rb
Last active April 11, 2023 14:11
void value expressions make no sense
-> { a = case when true then return end } # this is allowed
-> { a = if true then return end } # this is not
-> { a = if true then return; 2 end } # this is
-> { a = (true && return) } # this is allowed
-> { a = (return && true) } # this is not
-> { a = begin; return
rescue; return
ensure; return
@dergachev
dergachev / GIF-Screencast-OSX.md
Last active October 26, 2025 18:48
OS X Screencast to animated GIF

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Screencapture GIF

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

@tototoshi
tototoshi / rownum.sql
Created December 26, 2012 01:14
Grouped LIMIT in PostgreSQL: show the first N rows for each group
-- http://stackoverflow.com/questions/1124603/grouped-limit-in-postgresql-show-the-first-n-rows-for-each-group
-- http://www.postgresql.jp/document/9.2/html/tutorial-window.html
CREATE TABLE empsalary (
depname varchar(10) not null
, empno integer not null
, salary integer not null
);
INSERT INTO empsalary (depname, empno, salary) VALUES ('develop', 11, 5200);