fixing

.gitignore

@@ -1,15 +1,15 @@
 # test coverage folder
-coverage
+/coverage/
 
 # npm modules
 # https://docs.npmjs.com/misc/faq#should-i-check-my-node-modules-folder-into-git
-node_modules
+/node_modules/
 
 # npm errors
 npm-debug.log
 
 # github pages
-gh-pages/
+/gh-pages/
 
 # for OS X users
 .DS_Store
@@ -23,7 +23,7 @@ gh-pages/
 *.sublime-workspace
 
 # webpack build target folder
-build-modules/
+/babel-transpiled-modules/
 
 # NUL
 NUL

.npmignore

@@ -5,16 +5,16 @@
 .travis.yml
 
 # test coverage folder
-coverage/
+/coverage/
 
 # npm errors
 npm-debug.log
 
 # github pages
-gh-pages/
+/gh-pages/
 
 # workspace files are user-specific
 *.sublime-workspace
 
 # NUL
-NUL
+/NUL

README.md

@@ -289,6 +289,10 @@ const style = styler`
 `
 ```
 
+### ES6
+
+This module is written in ES6/ES7 syntax and therefore requires [Babel](https://babeljs.io/) transpilation to support all the web browsers (not only the modern ones). Using [Babel](https://babeljs.io/) for ES6/ES7 transpilation in web development workflow is a common practice nowadays so just in case you happen to never used it in your projects - start using it now. It works everywhere: command line, Webpack, Browserify, whatever. In case you don't want to use Babel in your workflow for whatever reason you can still grab an already transpiled and concatenated build from the `build` folder.
+
 ### What's next
 
 I can add the features you want (or you can do it). I can work on making errors more user friendly and helpful if anyone else uses this module.

build-modules/helpers.js

@@ -0,0 +1,119 @@
+// if the variable is defined
+'use strict';
+
+Object.defineProperty(exports, '__esModule', {
+	value: true
+});
+exports.starts_with = starts_with;
+exports.ends_with = ends_with;
+exports.repeat = repeat;
+exports.is_blank = is_blank;
+exports.zip = zip;
+exports.extend = extend;
+var exists = function exists(what) {
+	return typeof what !== 'undefined';
+};
+
+exports.exists = exists;
+// if the string starts with the substring
+
+function starts_with(string, what) {
+	return string.indexOf(what) === 0;
+}
+
+// if the string ends with the substring
+
+function ends_with(string, what) {
+	var index = string.lastIndexOf(what);
+	if (index < 0) {
+		return;
+	}
+	return index === string.length - what.length;
+}
+
+// repeat string N times
+
+function repeat(what, times) {
+	var result = '';
+	while (times > 0) {
+		result += what;
+		times--;
+	}
+	return result;
+}
+
+// if the text is blank
+
+function is_blank(text) {
+	return !exists(text) || !text.replace(/\s/g, '');
+}
+
+// zips two arrays
+
+function zip(a, b) {
+	return a.map(function (_, index) {
+		return [a[index], b[index]];
+	});
+}
+
+// extends the first object with
+/* istanbul ignore next: some weird transpiled code, not testable */
+
+function extend() {
+	var _this = this,
+	    _arguments = arguments;
+
+	var _again = true;
+
+	_function: while (_again) {
+		_len = objects = _key = to = from = last = intermediary_result = _iteratorNormalCompletion = _didIteratorError = _iteratorError = undefined;
+		_again = false;
+
+		for (var _len = _arguments.length, objects = Array(_len), _key = 0; _key < _len; _key++) {
+			objects[_key] = _arguments[_key];
+		}
+
+		var to = objects[0];
+		var from = objects[1];
+
+		if (objects.length > 2) {
+			var last = objects.pop();
+			var intermediary_result = extend.apply(_this, objects);
+			_this = undefined;
+			_arguments = [intermediary_result, last];
+			_again = true;
+			continue _function;
+		}
+
+		var _iteratorNormalCompletion = true;
+		var _didIteratorError = false;
+		var _iteratorError = undefined;
+
+		try {
+			for (var _iterator = Object.keys(from)[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+				var key = _step.value;
+
+				if (typeof from[key] === 'object' && exists(to[key])) {
+					to[key] = extend(to[key], from[key]);
+				} else {
+					to[key] = from[key];
+				}
+			}
+		} catch (err) {
+			_didIteratorError = true;
+			_iteratorError = err;
+		} finally {
+			try {
+				if (!_iteratorNormalCompletion && _iterator['return']) {
+					_iterator['return']();
+				}
+			} finally {
+				if (_didIteratorError) {
+					throw _iteratorError;
+				}
+			}
+		}
+
+		return to;
+	}
+}