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Learn JavaScript concepts with the Chrome DevTools

Authored by Peter Rybin , Chrome DevTools team

In this short guide we'll review some new Chrome DevTools features for "function scope" and "internal properties" by exploring some base JavaScript language concepts.

Closures

Let's start with closures – one of the most famous things in JS. A closure is a function, that uses variables from outside. See an example:

Tales From a Heroku User

Here are some things I have learned along the way.

Last Updated: 2013-02-08

Original Audience: Hack Reactor

About

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

-E: will describe the underlaying queries of the \ commands (cool for learning!)
-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

ABOUT

about:config settings to harden the Firefox browser. Privacy and performance enhancements.
To change these settings type 'about:config' in the url bar. Then search the setting you would like to change and modify the value. Some settings may break certain websites from functioning and rendering normally. Some settings may also make firefox unstable. I am not liable for any damages/loss of data.

Not all these changes are necessary and will be dependent upon your usage and hardware. Do some research on settings if you don't understand what they do. These settings are best combined with your standard privacy extensions (~~HTTPS Everywhere~~ No longer required: Enable HTTPS-Only Mode, NoScript/Request Policy, uBlock origin, agent spoofing, ~~Privacy Badger~~ etc), and all plugins set to "Ask To Activate".

Inheritance is a key concept in most object-oriented languages, but applying it skillfully can be challenging in practice. Back in 1989, M. Sakkinen wrote a paper called Disciplined inheritance that addresses these problems and offers some useful criteria for working around them. Despite being more than two decades old, this paper is extremely relevant to the modern Ruby programmer.

Sakkinen's central point seems to be that most traditional uses of inheritance lead to poor encapsulation, bloated object contracts, and accidental namespace collisions. He provides two patterns for disciplined inheritance and suggests that by normalizing the way that we model things, we can apply these two patterns to a very wide range of scenarios. He goes on to show that code that conforms to these design rules can easily be modeled as ordinary object composition, exposing a solid alternative to tradi

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	Copyright (C) 2011 Mathieu 'p01' Henri <http://www.p01.org/releases/>

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	DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE

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	The MIT License (MIT)

	Copyright (c) 2015 Justin Perry

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	var alphabet = 'abcdefghijklmnopqrstuvwxyz'.split(''),
	stringLen = Math.floor(Math.random() * (maxLen - minLen + 1)) + minLen,
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