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@davidphasson
davidphasson / show.html.erb
Created April 8, 2009 03:42
ERB and the case statement
# Doesn't work
<p>
<% case @request.author_hosted %>
<% when "yes" %>
The school <b>has</b> hosted an author before.
<% when "no" %>
The school <b>has not</b> hosted an author before.
<% end %>
</p>
@jfarmer
jfarmer / 01-truthy-and-falsey-ruby.md
Last active March 5, 2025 10:26
True and False vs. "Truthy" and "Falsey" (or "Falsy") in Ruby, Python, and JavaScript

true and false vs. "truthy" and "falsey" (or "falsy") in Ruby, Python, and JavaScript

Many programming languages, including Ruby, have native boolean (true and false) data types. In Ruby they're called true and false. In Python, for example, they're written as True and False. But oftentimes we want to use a non-boolean value (integers, strings, arrays, etc.) in a boolean context (if statement, &&, ||, etc.).

This outlines how this works in Ruby, with some basic examples from Python and JavaScript, too. The idea is much more general than any of these specific languages, though. It's really a question of how the people designing a programming language wants booleans and conditionals to work.

If you want to use or share this material, please see the license file, below.

Update

@andreyvit
andreyvit / tmux.md
Created June 13, 2012 03:41
tmux cheatsheet

tmux cheat sheet

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

remap prefix to Control + a

@MohamedAlaa
MohamedAlaa / tmux-cheatsheet.markdown
Last active October 31, 2025 20:47
tmux shortcuts & cheatsheet

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname
@dholbrook
dholbrook / Tree.scala
Created June 21, 2012 17:59
Scala binary tree
/**
* D Holbrook
*
* Code Club: PO1
*
* (*) Define a binary tree data structure and related fundamental operations.
*
* Use whichever language features are the best fit (this will depend on the language you have selected). The following operations should be supported:
*
* Constructors
def countChange(money: Int, coins: List[Int]): Int =
if (money < 0 || coins.isEmpty)
0
else if (money == 0)
1
else
countChange(money - coins.head, coins) + countChange(money, coins.tail)
@loicdescotte
loicdescotte / Forcomptran.md
Last active May 27, 2023 06:27
Scala for comprehension translation helper

Scala for comprehension translation helper

"For comprehension" is a another syntaxe to use map, flatMap and withFilter (or filter) methods.

yield keyword is used to aggregate values in the resulting structure.

This composition can be used on any type implementing this methods, like List, Option, Future...

@ryansobol
ryansobol / gist:5252653
Last active February 23, 2025 06:28
15 Questions to Ask During a Ruby Interview

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

@willurd
willurd / web-servers.md
Last active October 30, 2025 23:18
Big list of http static server one-liners

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000
@tomas-stefano
tomas-stefano / Capybara.md
Last active July 2, 2025 01:57
Capybara cheatsheet

Capybara Actions

# Anchor
click_link 'Save'

# Button
click_button 'awesome'

# Both above