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@egonSchiele
egonSchiele / canny.cpp
Created December 28, 2010 02:42
Adding automatic thresholding to cvCanny in OpenCV
// new
/*M///////////////////////////////////////////////////////////////////////////////////////
//
// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
// By downloading, copying, installing or using the software you agree to this license.
// If you do not agree to this license, do not download, install,
// copy or use the software.
//
//
@krasserm
krasserm / jaxb-01.scala
Created February 23, 2012 08:23
JAXB-based XML and JSON APIs
import javax.xml.bind.annotation._
@XmlRootElement(name = "person")
@XmlAccessorType(XmlAccessType.FIELD)
case class Person(fullname: String, username: Option[String], age: Int)
@jroper
jroper / MyManagedResource.scala
Last active November 4, 2021 10:20
Play resource routing
class MyManagedResource extends ResourceController[String] {
def index = Action(Ok("index"))
def newScreen = Action(Ok("new"))
def create = Action {
Redirect(MyInjectableResource.reverseRoutes.index())
}
def show(id: String) = Action(Ok("Show " + id))
@vrischmann
vrischmann / .credentials
Last active January 20, 2023 11:57
Running SBT with a Nexus proxy with authentication
realm=Sonatype Nexus Repository Manager
host=nexus.company.com
user=admin
password=admin123
@caoilte
caoilte / jaxb-in-scala-2_01.scala
Last active August 29, 2015 14:06
Bending JAXB to the will of Scala [2/2]
import scala.annotation.target.field
import javax.xml.bind.annotation._
import javax.xml.bind.annotation.adapters._
type xmlElement = XmlElement @field
type xmlTypeAdapter = XmlJavaTypeAdapter @field
/**
* NB As with the CustomOptionAdapter we've had to modify the type signature here,
@knutwalker
knutwalker / FSM.scala
Last active April 3, 2022 13:51
Simple Encoding of a purely functional Finite State Machine using Scala and scalaz
package example.statemachine
import scalaz.{State, Scalaz}, Scalaz._
object FSM {
def apply[I, S](f: PartialFunction[(I, S), S]): FSM[I, S] =
new FSM((i, s) => f.applyOrElse((i, s), (_: (I, S)) => s))
private def states[S, O](xs: List[State[S, O]]): State[S, List[O]] =
xs.sequence[({type λ[α]=State[S, α]})#λ, O]
@mikelehen
mikelehen / generate-pushid.js
Created February 11, 2015 17:34
JavaScript code for generating Firebase Push IDs
/**
* Fancy ID generator that creates 20-character string identifiers with the following properties:
*
* 1. They're based on timestamp so that they sort *after* any existing ids.
* 2. They contain 72-bits of random data after the timestamp so that IDs won't collide with other clients' IDs.
* 3. They sort *lexicographically* (so the timestamp is converted to characters that will sort properly).
* 4. They're monotonically increasing. Even if you generate more than one in the same timestamp, the
* latter ones will sort after the former ones. We do this by using the previous random bits
* but "incrementing" them by 1 (only in the case of a timestamp collision).
*/
@odd
odd / LocalExecutor.scala
Last active May 25, 2019 15:27
LocalExecutor allows executing callback code locally inside an actor (where the actor state can be safely modified)
import akka.actor._
import scala.concurrent.duration.Duration
import scala.concurrent.{CanAwait, ExecutionContext, Future, TimeoutException}
import scala.util.{Failure, Success, Try}
object LocalExecutor {
private case class Execute(runnable: Try[Runnable])
private class LocalExecutionContext(target: ActorRef) extends ExecutionContext {
override def execute(r: Runnable) = target ! Execute(Try(r))
@gnachman
gnachman / iterm.scpt
Last active April 8, 2023 23:42
Replace /Applications/Docker/Docker Quickstart Terminal.app/Contents/Resources/Scripts/iterm.scpt with this.
set itermRunning to (application "iTerm" is running)
set scriptPath to quoted form of POSIX path of ((path to me as text) & "::" & "start.sh")
set user_shell to do shell script "dscl /Search -read /Users/$USER UserShell | awk '{print $2}'"
tell application "iTerm"
activate
if not (exists window 1) or (itermRunning = false) then
reopen
end if
anonymous
anonymous / we-are-the-cure.md
Created April 15, 2016 20:49

Explaining Miles's Magic

Miles Sabin recently opened a pull request fixing the infamous SI-2712. First off, this is remarkable and, if merged, will make everyone's life enormously easier. This is a bug that a lot of people hit often without even realizing it, and they just assume that either they did something wrong or the compiler is broken in some weird way. It is especially common for users of scalaz or cats.

But that's not what I wanted to write about. What I want to write about is the exact semantics of Miles's fix, because it does impose some very specific assumptions about the way that type constructors work, and understanding those assumptions is the key to getting the most of it his fix.

For starters, here is the sort of thing that SI-2712 affects:

def foo[F[_], A](fa: F[A]): String = fa.toString