From 9da3919ca34eb6b38749e3fd674cd77558c4de88 Mon Sep 17 00:00:00 2001
From: Ovsky Aleksander <masterguyver@gmail.com>
Date: Mon, 23 Dec 2019 17:06:22 +0200
Subject: [PATCH] Task 1 and 2. In two task question. If I replaced   "const f
 = x =>" on "const f = function( x )". May I use operator this in 
 "Object.assign(f, { on })"?

---
 Exercises/1-pipe.js    |  7 ++++++-
 Exercises/2-compose.js | 25 ++++++++++++++++++++++++-
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/Exercises/1-pipe.js b/Exercises/1-pipe.js
index d09882a..0107e2c 100644
--- a/Exercises/1-pipe.js
+++ b/Exercises/1-pipe.js
@@ -1,5 +1,10 @@
 'use strict';
+const pipe = (...fns) => {
+  if (!fns.reduce((g, f) => typeof f === 'function' && g, true)) {
+    throw new Error('Not a function');
+  }
 
-const pipe = (...fns) => x => null;
+  return g => fns.reduce((g, f) => f(g), g);
+};
 
 module.exports = { pipe };
diff --git a/Exercises/2-compose.js b/Exercises/2-compose.js
index 368e521..d52eace 100644
--- a/Exercises/2-compose.js
+++ b/Exercises/2-compose.js
@@ -1,5 +1,28 @@
 'use strict';
 
-const compose = (...fns) => x => null;
+const compose = (...fns) => {
+  const events = { };
+  const emit = (event, ...args) => {
+    events[event](args);
+  };
+  const f = x => {
+    let res = x;
+    try {
+      for (const f of fns.reverse()) {
+        res = f(res);
+      }
+    } catch (e) {
+      emit('error', e);
+      return undefined;
+    }
+    return res;
+  };
+
+  const on = (event, callback) => {
+    events[event] = callback;
+  };
+  Object.assign(f, { on });
+  return f;
+};
 
 module.exports = { compose };