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-- This gist shows how we can use abilities to provide nicer syntax for any monad.
-- We can view abilities as "just" providing nicer syntax for working with the
-- free monad.

ability Monadic f where
  eval : f a -> a

-- Here's a monad, encoded as a first-class value with
-- two polymorphic functions, `pure` and `bind`
type Monad f = Monad (forall a . a -> f a) (forall a b . f a -> (a -> f b) -> f b)

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Unison transcript files

This is a Unison transcript file. It's used for creating typechecked documentation, test cases, and scripts.

It's just a markdown file that does some special interpretation of certain fenced code blocks. It can be passed to ucm as a command line argument. ucm will run through the file change events and commands in the file in order and output a new .md file with the responses to these inputs. It exits when it's done, so this can also be used for scripting.

Basics

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-- X filter
--  -- maybe some tests with List.all and List.any
-- 
-- intersperse
-- X head
-- X isEmpty
-- X tail
-- X init
-- X last

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ability State s where
  put : s ->{State s} ()
  get : {State s} s

state : s -> Effect (State s) a -> a
state s eff = case eff of
  { State.get -> k } -> handle (state s) in k s
  { State.put snew -> k } -> handle (state snew) in k ()
  { a } -> a

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--langdef=scala
--langmap=scala:.scala
--regex-scala=/^[ \t]*((abstract|final|sealed|implicit|lazy)[ \t]*)*(private|protected)?[ \t]*class[ \t]+([a-zA-Z0-9_]+)/\4/c,classes/
--regex-scala=/^[ \t]*((abstract|final|sealed|implicit|lazy)[ \t]*)*(private|protected)?[ \t]*object[ \t]+([a-zA-Z0-9_]+)/\4/c,objects/
--regex-scala=/^[ \t]*((abstract|final|sealed|implicit|lazy)[ \t]*)*(private|protected)?[ \t]*case class[ \t]+([a-zA-Z0-9_]+)/\4/c,case classes/
--regex-scala=/^[ \t]*((abstract|final|sealed|implicit|lazy)[ \t]*)*(private|protected)?[ \t]*case object[ \t]+([a-zA-Z0-9_]+)/\4/c,case objects/
--regex-scala=/^[ \t]*((abstract|final|sealed|implicit|lazy)[ \t]*)*(private|protected)?[ \t]*trait[ \t]+([a-zA-Z0-9_]+)/\4/t,traits/
--regex-scala=/^[ \t]*type[ \t]+([a-zA-Z0-9_]+)/\1/T,types/
--regex-scala=/^[ \t]*((@annotation.tailrec|@tailrec|@inline)[ \t]*)*((abstract|final|sealed|implicit|lazy|private|protected)[ \t]*)*def[ \t]+([a-zA-Z0-9_]+)/\5/m,methods/
--regex-scala=/^[ \t]*((abstract|final|sealed|implicit|la

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package scalaworld.interpreters

/*
This file shows a simple language, an interpreter, and two
partial evaluators for that language, along with a profiling suite.
*/

trait Expr // denotes a Vector[Double] => Vector[Double]

object Expr {

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object QuickProfile {

  def timeit(label: String, threshold: Double = 0.05)(action: => Long): (String, Double) = {
    var N = 16L
    var i = 0
    var startTime = System.nanoTime
    var stopTime = System.nanoTime
    var sample = 1e9
    var K = 0L
    var ok = true

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data Free f r 
  = Pure r 
  | Fail Err 
  | Eval (f r)
  | forall x . Bind (Free f x) (Either Err x -> Free f r)

type Pull f o r = Free (StreamF o) r

data StreamF o x where

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package fastcodecs

import java.nio.{ByteBuffer, BufferUnderflowException}

abstract class Decoder[+A] {
  /**
   * Read a value from the `ByteBuffer`, advancing the offset if successful.
   * Result is stored in `result`, unboxed if possible.
   * On failure, a `DecodingFailure` is thrown.
   */

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{-# Language ExistentialQuantification #-}
{-# Language GADTs #-}
{-# Language RankNTypes #-}
{-# Language ScopedTypeVariables #-}

import Control.Monad
import Control.Applicative
import Data.List hiding (uncons)
import Data.Time