1 and 2 done

Exercises/1-pipe.js

@@ -1,5 +1,10 @@
 'use strict';
 
-const pipe = (...fns) => x => null;
+const pipe = (...fns) => {
+  fns.forEach(x => {
+    if (typeof x !== 'function') throw new Error('arg must be a function');
+  });
+  return num => fns.reduce((val, fn) => fn(val), num);
+};
 
 module.exports = { pipe };

Exercises/2-compose.js

@@ -1,5 +1,21 @@
 'use strict';
 
-const compose = (...fns) => x => null;
+const compose = (...fns) => {
+  const events = {};
+  const fn = num => fns.reverse().reduce((val, f) => {
+    try {
+      if (typeof val === 'undefined') return undefined;
+      return f(val);
+    } catch (e) {
+      const err = events['error'];
+      if (err) err(e);
+      return undefined;
+    }
+  }, num);
+  fn.on = (event, callback) => {
+    events[event] = callback;
+  };
+  return fn;
+};
 
 module.exports = { compose };