travisbrown

object test {
  trait M[X[_]] {
    def map[A, B](a: X[A])(f: A => B): X[B]
  }

  trait Parsers {
    trait Parser[Y] {
      def map[B](f: Y => B): Parser[B] = null
    }
  }

travisbrown

object test {
  trait M[X[_]] {
    def map[A, B](a: X[A])(f: A => B): X[B]
  }

  trait Parsers {
    trait Parser[Y] {
      def map[B](f: Y => B): Parser[B] = null
    }
  }

travisbrown

import org.jscience.mathematics.number.LargeInteger

import com.google.caliper.{ Param, SimpleBenchmark }

class FactorialBenchmark extends SimpleBenchmark {

  // Borrowed from https://github.com/sirthias/scala-benchmarking-template.
  def repeat[@specialized A](reps: Int)(snippet: => A) = {
    val zero = 0.asInstanceOf[A]
    var i = 0

travisbrown

import dispatch._
import java.io.ByteArrayInputStream
import java.util.zip.ZipInputStream
import scala.util.parsing.json.JSON.{ parseFull => parseJson }

val headers = Map("content-type" -> "application/x-www-form-urlencoded")
val tokenUrl = url("https://silvermaple.pti.indiana.edu:25443/oauth2/token")
val volumesUrl = url("https://silvermaple.pti.indiana.edu:25443/data-api/volumes/")

def tokenParams(id: String, secret: String) = Map(

travisbrown

scala> import scalaz._, Scalaz._
import scalaz._
import Scalaz._

scala> val a: String \/ Int = "x".left
a: scalaz.\/[String,Int] = -\/(x)

scala> val b: String \/ Int = "y".left
b: scalaz.\/[String,Int] = -\/(y)

travisbrown

import scala.util.parsing.combinator._
import scalaz._, Scalaz._

trait ExtraStateParsers[S] { this: Parsers =>
  type ESP[A] = StateT[Parser, S, A]

  protected implicit def monadInstance: Monad[Parser]
  protected implicit def monadStateInstance =
    implicitly[MonadState[({type F[T, +B] = StateT[Parser, T, B]})#F, S]]

travisbrown

import scala.util.parsing.combinator._
import scalaz._, Scalaz._

trait ExtraStateParsers[S] { this: Parsers =>
  type ESP[A] = StateT[Parser, S, A]

  protected implicit def monadInstance: Monad[Parser]
  protected implicit def monadStateInstance =
    implicitly[MonadState[({type F[T, +B] = StateT[Parser, T, B]})#F, S]]

travisbrown

/**
 * We can use the Scala type system (with help from Miles Sabin's Shapeless
 * library) to solve the bank account number validation problem in the second
 * user story of the KataBankOCR kata on Coding Dojo:
 * 
 * http://codingdojo.org/cgi-bin/wiki.pl?KataBankOCR
 * 
 * By Travis Brown in response to a question by Paul Snively on the Shapeless
 * Dev mailing list:
 *

travisbrown

/**
* Type-level Tower of Hanoi
* by Travis Brown
*
* Note: not optimal, and probably won't work for some valid inputs.
* Tested with Scala 2.9.2 and Shapeless 1.2.3.
*/

import shapeless._, Nat._

travisbrown

import shapeless._

trait Flatten[I, O <: HList] {
  def apply(i: I): O
}

trait FlattenLow {
  implicit def otherFlatten[I] = new Flatten[I, I :: HNil] {
    def apply(i: I) = i :: HNil
  }