zraffer

package object types {

  import scala.language.reflectiveCalls
  import scala.language.higherKinds

  // quantifiers aka (co)ends
  type Forall[+F[_]] = { def apply[X]: F[X] }
  type Exists[+F[_]] = F[_]

  // basic categorical notions

djspiewak

Introduction to scalaz-stream

Every application ever written can be viewed as some sort of transformation on data. Data can come from different sources, such as a network or a file or user input or the Large Hadron Collider. It can come from many sources all at once to be merged and aggregated in interesting ways, and it can be produced into many different output sinks, such as a network or files or graphical user interfaces. You might produce your output all at once, as a big data dump at the end of the world (right before your program shuts down), or you might produce it more incrementally. Every application fits into this model.

The scalaz-stream project is an attempt to make it easy to construct, test and scale programs that fit within this model (which is to say, everything). It does this by providing an abstraction around a "stream" of data, which is really just this notion of some number of data being sequentially pulled out of some unspecified data source. On top of this abstraction, sca

Mzk-Levi

  trait Functor[F[_]] {
    def map[A, B](as: F[A])(f: A => B): F[B]
  }
  
  object Functor {
    def apply[F[_]](implicit e: Functor[F]): Functor[F] = e
  }
  
  trait ~>[F[_], G[_]] {
    def apply[A](x: F[A]): G[A]

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

arosien

import scalaz._
import Scalaz._
import Free._

/** "Pure" interactions with a console. */
sealed trait Console[+A]
case class GetLine[A](k: String => A) extends Console[A]
case class PutLine[A](s: String, a: A) extends Console[A]

object Console {

xian

You need to add the files below, and do this once in your base test runner:

ActionBarSherlock.registerImplementation(ActionBarSherlockRobolectric.class);
ActionBarSherlock.unregisterImplementation(ActionBarSherlockNative.class);
ActionBarSherlock.unregisterImplementation(ActionBarSherlockCompat.class);

rgreenjr

-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

shangaslammi

import Control.Exception
import Control.Monad
import Control.Monad.IO.Class
import Data.ByteString.Lazy (ByteString)
import Data.ByteString.Lazy.UTF8 (toString)
import Data.Function
import Data.Enumerator
import Data.List
import Data.Maybe

hagenburger

// Example:

JavaScript.load("/javascripts/something.js");


// With callback (that’s the good thing):

JavaScript.load("http://www.someawesomedomain.com/api.js", function() {
  API.use(); // or whatever api.js provides ...
});