john-kurkowski

➜ scala
Picked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF-8
Welcome to Scala version 2.10.3 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_21).
Type in expressions to have them evaluated.
Type :help for more information.

scala> case object Table extends Exception
defined module Table

scala> def ╯°□°╯┻┻ = throw Table

john-kurkowski

#!/bin/bash
# Compare Mac OS X 10.6's `sort` to latest GNU Coreutils `sort` which parallelizes by default.
# More info: http://www.cs.ucla.edu/classes/fall10/cs35L/assign/assign9.html

integers=10000000
file=`eval echo "~/Documents/integers1.txt"`

echo "Generating $integers integers..."
if [ ! -f $file ]; then
  for i in $(eval echo "{1..$integers}"); do

john-kurkowski

scala> val m = Map(1 -> 2, 3 -> 4, 5 -> 6)
map: scala.collection.immutable.Map[Int,Int] = Map((1,2), (3,4), (5,6))

scala> val desiredKeys = Iterable(1, 2, 3)
desiredKeys: Iterable[Int] = List(1, 2, 3)

// Get several values out of a Map, or a default.

scala> desiredKeys map (m.getOrElse(_, -1))
res0: Iterable[Int] = List(2, -1, 4)

john-kurkowski

def timeit(fn: () => Any, times: Int = 100000) {
  val start = System.currentTimeMillis
  for (_ <- 0 until times) {
    fn()
  }
  val end = System.currentTimeMillis
  println((end - start) + "ms")
}

val n = 10000

john-kurkowski

import org.semver.Version

val li = List(Version.parse("2.0.34"), Version.parse("1.1.0"), Version.parse("1.0.1"), Version.parse("34.1"))
// li: List[org.semver.Version] = List(2.0.4, 1.1.0, 1.0.1, 4.1.0) // HUH?

println(li.sorted)
// List(4.1.0, 2.0.4, 1.1.0, 1.0.1) // reversed!

john-kurkowski

(defn try-times-wait-millis* [times wait-millis thunk]
  (let [attempts (repeatedly times
                            #(try (thunk)
                                  (catch Exception ex (do
                                                        (Thread/sleep wait-millis)
                                                        {::failure ex}))))
        successes (drop-while #(contains? % ::failure) attempts)]

    (if (not (empty? successes))
        {:success (first successes)}

john-kurkowski

class SlidingWindowMap(keys: Set[String], maxCount: Int, periodMs: Int) {

  val times = new collection.mutable.HashMap[String, Vector[Long]]() with collection.mutable.SynchronizedMap[String, Vector[Long]]
  times ++= keys.map(k => (k, Vector[Long]()))

  def nextKey: Option[String] = {
    val now = System.currentTimeMillis
    times.synchronized {
      val trimmedTimes = times.toStream map { case (k, usage) =>
        val trimmedUsage = usage dropWhile (_ < now - periodMs)

john-kurkowski

Fault Tolerance: Software is Ruining the Human Experience

Mostly a rant on a few bad experiences that could have been prevented in real life if engineers did a good job instead of a good enough job. We have no oath to "Do no harm!" So, we take license to ship whatever. This is bad for humans.

Intro: Fault Tolerance and Bad Human Experiences

Pumping Up the Tires

1. Wow look new technology, pumping up tires is way better now
2. Not so much, they added software to the process, oops

john-kurkowski

#!/usr/bin/env python

'''Convert tags with no leading "v" to NPM's default tag format.'''

import re
import subprocess


OLD_TAG_RE = re.compile(r'^\d+\.\d+')

john-kurkowski

{
    "basePath": "/v2",
    "definitions": {
        "ApiResponse": {
            "properties": {
                "code": {
                    "format": "int32",
                    "type": "integer"
                },
                "message": {