rust-play

struct Alpha {}

trait Beta {
    fn p(&self, z: &Beta) -> bool;
}

trait Gamma: Beta {}

impl Beta for Alpha {

itaysk

curl -L --fail "https://hub.docker.com/v2/repositories/${DOCKERHUB_REPO}/${DOCKERHUB_IMAGE}/tags/?page_size=1000" | \
	jq '.results | .[] | .name' -r | \
	sed 's/latest//' | \
	sort --version-sort | \
	tail -n 1

jFransham

Achieving warp speed with Rust

Contents:

• Number one optimization tip: don't
• Never optimize blindly
• Don't bother optimizing one-time costs
• Improve your algorithms
• CPU architecture primer
• Keep as much as possible in cache
• Keep as much as possible in registers

KodrAus

Profiling performance

Using perf:

$ perf record -g binary
$ perf script | stackcollapse-perf.pl | rust-unmangle | flamegraph.pl > flame.svg

NOTE: See @GabrielMajeri's comments below about the -g option.

ipbastola

Safest way to clean up boot partition - Ubuntu 14.04LTS-x64, Ubuntu 16.04LTS-x64

Reference

Case I: if /boot is not 100% full and apt is working

1. Check the current kernel version

$ uname -r 

petrkohut

How to install redis-cli and psql client on your machine with Docker

Preparing docker images

We will use minimalistic Linux distribution called Alpine (5MB)

Dockerfile of redis-cli

FROM alpine:latest
RUN apk --update add redis

mbreese

docker run  -v /Users/mbreese/tmp:/tmp1 -w /tmp1 -i centos:7 /bin/bash -s <<EOF 
date > foo
echo 'foo' >> foo
cat /etc/redhat-release >> foo
whoami >> foo
EOF

phrawzty

#!/usr/bin/env python2

import SimpleHTTPServer
import SocketServer
import logging

PORT = 8000

class GetHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):

abn

#printf
RUN printf '#!/bin/bash\n\
echo hello world from line 1\n\
echo hello world from line 2'\
>> /tmp/hello

#echo
RUN echo -e '#!/bin/bash\n\
echo hello world from line 1\n\
echo hello world from line 2'\

nikomatsakis

The "Hashtable Problem"

There is a danger with typeclasses only on functions because they permit a lack of coherence. This danger is particularly acute with collections, where the definition of a particular interface---such as hashable or ord---may be used in structuring the data structure. This renders the data structure corrupt when used with a different implementation.

To see the problem, consider a hashtable defined something like this: