From cc4c2c9736f86d192bdc3d9ecb806e2125abd8e3 Mon Sep 17 00:00:00 2001
From: ser <ser@localhost.localdomain>
Date: Fri, 22 Nov 2019 08:27:16 +0200
Subject: [PATCH 1/2] work, but some tests failed

---
 Exercises/1-pipe.js     |  7 ++++++-
 Exercises/2-compose.js  | 25 ++++++++++++++++++++++-
 Exercises/2-compose2.js | 45 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+), 2 deletions(-)
 create mode 100644 Exercises/2-compose2.js

diff --git a/Exercises/1-pipe.js b/Exercises/1-pipe.js
index d09882a..37ee6af 100644
--- a/Exercises/1-pipe.js
+++ b/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 };
diff --git a/Exercises/2-compose.js b/Exercises/2-compose.js
index 368e521..3244067 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 fn = num => {
+    return fns.reverse().reduce((val, fn) => {
+      try {
+        return fn(val);
+      } catch (e) {
+        fn.emmit('error', e)
+        return undefined;
+      }
+    }, num);
+  };
+  fn.on = (event, callback) => {
+    let res = events[event];
+    if (!res) res = [];
+    res.push(callback);
+    events[event] = res;
+  }
+  fn.emmit = (event, ...args) => {
+    const res = events[event];
+    if (res) res.forEach(callback => callback(...args));
+  }
+  return fn;
+};
 
 module.exports = { compose };
diff --git a/Exercises/2-compose2.js b/Exercises/2-compose2.js
new file mode 100644
index 0000000..69cbd37
--- /dev/null
+++ b/Exercises/2-compose2.js
@@ -0,0 +1,45 @@
+'use strict';
+
+const compose = (...fns) => {
+  const events = {};
+  const err = [];
+  fns.forEach(x => {
+    if (typeof x !== 'function') {
+      err.push(new Error(`${x} not a function`));
+    };
+  });
+  const fn = num => {
+    if (err) fn.emmit('error', err);
+    return fns.reduce((val, fn) => {
+      if (typeof fn === 'function') {
+        return fn(val);
+      } else return undefined;
+    }, num);
+  };
+  fn.on = (event, callback) => {
+    let res = events[event];
+    if (!res) res = [];
+    res.push(callback);
+    events[event] = res;
+  }
+  fn.emmit = (event, ...args) => {
+    const res = events[event];
+    if (res) {
+      res.forEach(callback => callback(...args));
+    }
+  }
+  return fn;
+};
+
+const inc = x => ++x;
+const twice = x => x * 2;
+const cube = x => x ** 3;
+const f1 = compose(inc, 7, 9);
+f1.on('error', err => {
+  console.log(err);
+});
+console.log(f1(5));
+const f2 = compose(inc, twice, cube);
+console.log(f2(5));
+
+module.exports = { compose };

From 678c1f1bc9e07a95aea729279cbe7234ceeab9b8 Mon Sep 17 00:00:00 2001
From: ser <ser@localhost.localdomain>
Date: Fri, 22 Nov 2019 21:14:22 +0200
Subject: [PATCH 2/2] done compose

---
 Exercises/2-compose.js  | 31 +++++++++++-----------------
 Exercises/2-compose2.js | 45 -----------------------------------------
 2 files changed, 12 insertions(+), 64 deletions(-)
 delete mode 100644 Exercises/2-compose2.js

diff --git a/Exercises/2-compose.js b/Exercises/2-compose.js
index 3244067..313baf8 100644
--- a/Exercises/2-compose.js
+++ b/Exercises/2-compose.js
@@ -2,26 +2,19 @@
 
 const compose = (...fns) => {
   const events = {};
-  const fn = num => {
-    return fns.reverse().reduce((val, fn) => {
-      try {
-        return fn(val);
-      } catch (e) {
-        fn.emmit('error', e)
-        return undefined;
-      }
-    }, num);
-  };
+  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) => {
-    let res = events[event];
-    if (!res) res = [];
-    res.push(callback);
-    events[event] = res;
-  }
-  fn.emmit = (event, ...args) => {
-    const res = events[event];
-    if (res) res.forEach(callback => callback(...args));
-  }
+    events[event] = callback;
+  };
   return fn;
 };
 
diff --git a/Exercises/2-compose2.js b/Exercises/2-compose2.js
deleted file mode 100644
index 69cbd37..0000000
--- a/Exercises/2-compose2.js
+++ /dev/null
@@ -1,45 +0,0 @@
-'use strict';
-
-const compose = (...fns) => {
-  const events = {};
-  const err = [];
-  fns.forEach(x => {
-    if (typeof x !== 'function') {
-      err.push(new Error(`${x} not a function`));
-    };
-  });
-  const fn = num => {
-    if (err) fn.emmit('error', err);
-    return fns.reduce((val, fn) => {
-      if (typeof fn === 'function') {
-        return fn(val);
-      } else return undefined;
-    }, num);
-  };
-  fn.on = (event, callback) => {
-    let res = events[event];
-    if (!res) res = [];
-    res.push(callback);
-    events[event] = res;
-  }
-  fn.emmit = (event, ...args) => {
-    const res = events[event];
-    if (res) {
-      res.forEach(callback => callback(...args));
-    }
-  }
-  return fn;
-};
-
-const inc = x => ++x;
-const twice = x => x * 2;
-const cube = x => x ** 3;
-const f1 = compose(inc, 7, 9);
-f1.on('error', err => {
-  console.log(err);
-});
-console.log(f1(5));
-const f2 = compose(inc, twice, cube);
-console.log(f2(5));
-
-module.exports = { compose };