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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.)
@timvisee
timvisee / falsehoods-programming-time-list.md
Last active April 26, 2024 04:52
Falsehoods programmers believe about time, in a single list

Falsehoods programmers believe about time

This is a compiled list of falsehoods programmers tend to believe about working with time.

Don't re-invent a date time library yourself. If you think you understand everything about time, you're probably doing it wrong.

Falsehoods

  • There are always 24 hours in a day.
  • February is always 28 days long.
  • Any 24-hour period will always begin and end in the same day (or week, or month).
@lelandbatey
lelandbatey / whiteboardCleaner.md
Last active April 25, 2024 02:01
Whiteboard Picture Cleaner - Shell one-liner/script to clean up and beautify photos of whiteboards!

Description

This simple script will take a picture of a whiteboard and use parts of the ImageMagick library with sane defaults to clean it up tremendously.

The script is here:

#!/bin/bash
convert "$1" -morphology Convolve DoG:15,100,0 -negate -normalize -blur 0x1 -channel RBG -level 60%,91%,0.1 "$2"

Results

@dhh
dhh / pagination_controller.js
Last active April 24, 2024 10:53
HEY's Stimulus Pagination Controller
/*
ERB template chunk from The Feed's display of emails:
<section class="postings postings--feed-style" id="postings"
data-controller="pagination" data-pagination-root-margin-value="40px">
<%= render partial: "postings/snippet", collection: @page.records, as: :posting, cached: true %>
<%= link_to(spinner_tag, url_for(page: @page.next_param),
class: "pagination-link", data: { pagination_target: "nextPageLink", preload: @page.first? }) unless @page.last? %>
</section>
@IanColdwater
IanColdwater / twittermute.txt
Last active April 22, 2024 17:26
Here are some terms to mute on Twitter to clean your timeline up a bit.
Mute these words in your settings here: https://twitter.com/settings/muted_keywords
ActivityTweet
generic_activity_highlights
generic_activity_momentsbreaking
RankedOrganicTweet
suggest_activity
suggest_activity_feed
suggest_activity_highlights
suggest_activity_tweet
@burke
burke / 0-readme.md
Created January 27, 2012 13:44 — forked from funny-falcon/cumulative_performance.patch
ruby-1.9.3-p327 cumulative performance patch for rbenv

ruby-1.9.3-p327 cumulative performance patch for rbenv

This installs a patched ruby 1.9.3-p327 with various performance improvements and a backported COW-friendly GC, all courtesy of funny-falcon.

Requirements

You will also need a C Compiler. If you're on Linux, you probably already have one or know how to install one. On OS X, you should install XCode, and brew install autoconf using homebrew.

@JunichiIto
JunichiIto / alias_matchers.md
Last active April 16, 2024 16:18
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
@coreyhaines
coreyhaines / .rspec
Last active April 11, 2024 00:19
Active Record Spec Helper - Loading just active record
--colour
-I app

Make it real

Ideas are cheap. Make a prototype, sketch a CLI session, draw a wireframe. Discuss around concrete examples, not hand-waving abstractions. Don't say you did something, provide a URL that proves it.

Ship it

Nothing is real until it's being used by a real user. This doesn't mean you make a prototype in the morning and blog about it in the evening. It means you find one person you believe your product will help and try to get them to use it.

Do it with style

@ldez
ldez / gmail-github-filters.md
Last active April 3, 2024 11:53
Gmail and GitHub - Filters

Gmail and GitHub

How to filter emails from GitHub in Gmail and flag them with labels.

The labels in this document are just examples.

Pull Request

Filter Label