James Dietrich jbdietrich

launchd - Script Management in macOS

What is it?

Used on macOS for managing agents and daemons and can be used to run scripts at specified intervals
- macOS's competitor to cron, along with other things
Runs Daemons and Agents

What is a Daemon?

using rust with rr

rr is a great debugging tool. it records a trace of a program's execution, as well as the results of any syscalls it executes, so that you can "rewind" while you debug, and get deterministic forward and reverse instrumented playback. it works with rust, but by default if you try it out, it could be pretty ugly when you inspect variables. if this bothers you, configure gdb to use a rust pretty-printer

rr is probably in your system's package manager.

usage

Currently, there is an explosion of tools that aim to manage secrets for automated, cloud native infrastructure management. Daniel Somerfield did some work classifying the various approaches, but (as far as I know) no one has made a recent effort to summarize the various tools.

This is an attempt to give a quick overview of what can be found out there. The list is alphabetical. There will be tools that are missing, and some of the facts might be wrong--I welcome your corrections. For the purpose, I can be reached via @maxvt on Twitter, or just leave me a comment here.

There is a companion feature matrix of various tools. Comments are welcome in the same manner.

emacs --daemon to run in the background. emacsclient.emacs24 <filename/dirname> to open in terminal

NOTE: "M-m and SPC can be used interchangeably".

Undo - C-/
Redo - C-?
Change case: 1. Camel Case : M-c 2. Upper Case : M-u

Lower Case : M-l

Document moved to: https://github.com/servo/servo/blob/master/HACKING_QUICKSTART.md

My summary of https://www.youtube.com/watch?v=IqrwPVtSHZI

TL;DR:

Rails has a library, ActiveSupport, which adds methods to Ruby core classes. One of those methods is String#blank?, which returns a boolean (sometimes I miss this convention in Rust, the ?) if the whole string is whitespace or not. It looks like this: https://github.com/rails/rails/blob/b3eac823006eb6a346f88793aabef28a6d4f928c/activesupport/lib/active_support/core_ext/object/blank.rb#L99-L117

It's pretty slow. So Discourse (which you may know from {users,internals}.rust-lang.org) uses the fast_blank gem, which provides this method via a C implementation instead. It looks like this: https://github.com/SamSaffron/fast_blank/blob/master/ext/fast_blank/fast_blank.c

For fun, Yehuda tried to re-write fast_blank in Rust. Which looks like this:

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics

elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

Abramsky and Jung "Domain Theory" http://www.cs.bham.ac.uk/~axj/pub/papers/handy1.pdf
Appel, Andrew "Modern Compiler Implementation in ML"
Cousot, Patrick "Abstract Interpretation Based Formal Methods and Future Challenges" http://www.di.ens.fr/~cousot/publications.www/Cousot-LNCS2000-sv-sb.pdf
Darais, Might, and Van Horn "Galois Transformers and Modular Abstract Interpreters" http://arxiv.org/pdf/1411.3962v1.pdf
Davey and Priestley, "Introduction To Lattices and Order"
Friedman and Mendhekar, "Using an Abstracted Interpreter to Understand Abstract Interpretation" http://www.cs.indiana.*du/l/www/classes/b621/abiall.pdf
Friedman and Wand, "Essentials of Programming Languages"
Jones and Nielson, "Abstract Interpretation: a Semantics-Based Tool for Program Analysis" http://se.inf.ethz.ch/courses/2014b_fall/sv/reading/jones-nielson.pdf
Livshits, Sridharan, Smaragdakis, et. al. "In Defense of Soundiness: A Manifesto" http://cgi.di.uoa.gr/~smaragd/Soundiness-CACM.pdf
Might, Matt "Writing an inte

	"""Perlin noise implementation."""
	# Licensed under ISC
	from itertools import product
	import math
	import random


	def smoothstep(t):
	"""Smooth curve with a zero derivative at 0 and 1, making it useful for
	interpolating.

	// From: https://www.reddit.com/r/rust/comments/2ow729/writing_a_lexer/
	use std::iter::Peekable;

	fn main() {
	let input = "abcdABCDabcd,".chars();

	let tokenizer = Tokenizer::new(input);

	for token in tokenizer {
	println!("{:?}", token);