Merge #9 - Add examples

Fix #4

Author: felixSchl

.travis.yml

@@ -13,3 +13,4 @@ install:
   - npm install
 script:
   - npm run build
+  - npm run example

README.md

@@ -7,3 +7,11 @@
 
 * @scott-christopher for porting `ListT` and writing the `MonadError`,
   `MonadWriter`, `MonadPlus` and `Alternative` instances for `Proxy`!
+
+## How-To
+
+For an in-depth overview of pipes follow the tutorial that comes with the
+Haskell pipes library. The concepts apply one to one to purescript-pipes.
+
+Also have a look at the examples that come with purescript-pipes. You can run
+them using `npm run example`.

bower.json

@@ -23,5 +23,9 @@
     "purescript-tailrec": "^3.0.0",
     "purescript-mmorph": "^3.0.0",
     "purescript-prelude": "^3.0.0"
+  },
+  "devDependencies": {
+    "purescript-console": "^3.0.0",
+    "purescript-random": "^3.0.0"
   }
 }

examples/Example.purs

@@ -0,0 +1,28 @@
+module Example where
+
+import Prelude
+import Control.Monad.Eff (Eff)
+import Control.Monad.Eff.Class (liftEff)
+import Control.Monad.Eff.Console (CONSOLE, log)
+import Control.Monad.Eff.Random (randomInt, RANDOM)
+
+import Pipes (yield, for)
+import Pipes.Core (runEffect, Producer_)
+
+pipedRandomInt
+  :: ∀ eff
+   . Int
+  -> Int
+  -> Producer_ String (Eff (random :: RANDOM | eff)) Int
+pipedRandomInt x y = do
+  yield $ "Generating an Int between " <> show x <> " and " <> show y <> "..."
+  r <- liftEff $ randomInt x y
+  yield $ "Generated " <> show r
+  pure r
+
+main :: Eff (console :: CONSOLE, random :: RANDOM) Unit
+main =
+  let go = pipedRandomInt 1 10
+   in do
+    r <- runEffect $ for go (liftEff <<< log <<< ("Log: " <> _))
+    log $ "Result: " <> show r

package.json

@@ -2,7 +2,8 @@
   "private": true,
   "scripts": {
     "postinstall": "bower install",
-    "build": "pulp build && rimraf docs && pulp docs"
+    "build": "pulp build && rimraf docs && pulp docs",
+    "example": "pulp run -I examples -I src -I bower_components -m example"
   },
   "devDependencies": {
     "bower": "^1.7.9",