jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

willurd

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

speric

                               Lesson 1 SUMMARY


  1. The cursor is moved using either the arrow keys or the hjkl keys.
         h (left)       j (down)       k (up)       l (right)

  2. To start Vim from the shell prompt type:  vim FILENAME <ENTER>

  3. To exit Vim type:     <ESC>   :q!   <ENTER>  to trash all changes.
             OR type:      <ESC>   :wq   <ENTER>  to save the changes.

gist:91865cb266659c2c3f24

'''A few notes before we begin

I'll separate my notes into three types, docstrings like this, whole line comments, and
inline comments. Docstrings will discuss the ideas behind the objects. What's the intent,
and what programming concepts do they present that are worth discussing. Full line comments
will discuss the details of the implementation. What the code is doing and why. Inline
comments will comprise a small portion of my notes, and are mostly to point out examples
mentioned in the rest of my notes, or return values. Another convention that I use is
backticks, which will be used to refer to an actual object in the code. If I say the word
one, it's just a word, but `one` is a reference to some object in code.

pgilad

Instructions

• copy the file commit-msg to .git/hooks/commit-msg
• make sure your delete the sample file .git/hooks/commit-msg.sample
• Make commit msg executable. chmod +x .git/hooks/commit-msg
• Edit commit-msg to better fit your development branch, commit regex and error message
• Profit $$

Shell example

joepie91

Not all random values are created equal - for security-related code, you need a specific kind of random value.

A summary of this article, if you don't want to read the entire thing:

• Don't use Math.random(). There are extremely few cases where Math.random() is the right answer. Don't use it, unless you've read this entire article, and determined that it's necessary for your case.
• Don't use crypto.getRandomBytes directly. While it's a CSPRNG, it's easy to bias the result when 'transforming' it, such that the output becomes more predictable.
• If you want to generate random tokens or API keys: Use uuid, specifically the uuid.v4() method. Avoid node-uuid - it's not the same package, and doesn't produce reliably secure random values.
• If you want to generate random numbers in a range: Use random-number-csprng.

You should seriously consider reading the entire article, though - it's

pydevops

• 0.1. References
• 0.2. Other cheatsheets
• 0.3. Manage multiple gcloud config configurations
  • 0.3.1. Switch gcloud context with gcloud config
• 0.4. Credentials
• 0.5. info
• 0.6. projects
• 0.7. zones & regions
• 0.8. Organization
• 0.9. billing

mrmartineau

Stimulus cheatsheet

• Website: https://stimulusjs.org/
• GitHub repo: https://github.com/stimulusjs/stimulus
• Handbook: https://stimulusjs.org/handbook/introduction
• Discourse: https://discourse.stimulusjs.org/

Lifecycle callbacks

• initialize: once, when the controller is first instantiated
• connect: anytime the controller is connected to the DOM

lhorie

So there were a few threads going around recently about a challenge to write the longest sequence of keywords in Javascript:

• https://twitter.com/bterlson/status/1093624668903268352
• https://news.ycombinator.com/item?id=19102367

There are, however, a few problems:

• These solutions use non-keyword tokens (null, true, false are actually Literals, not Keywords)
• One of the solutions isn't quite valid (new super)

zed-dz

Offline MDN Docs

If you want resources offline to learn about programming and web technologies MDN is for you! and I recommend to use MDN over w3school because w3school is outdated.

full tarball download

Download it offline (2.1gb) at https://mdn-downloads.s3-us-west-2.amazonaws.com/developer.mozilla.org.tar.gz

Third-party toolsSection