--- /dev/null
+'use strict';
+
+/**
+ * Module dependencies
+ */
+
+exports.extend = require('extend-shallow');
+exports.SourceMap = require('source-map');
+exports.sourceMapResolve = require('source-map-resolve');
+
+/**
+ * Convert backslash in the given string to forward slashes
+ */
+
+exports.unixify = function(fp) {
+ return fp.split(/\\+/).join('/');
+};
+
+/**
+ * Return true if `val` is a non-empty string
+ *
+ * @param {String} `str`
+ * @return {Boolean}
+ */
+
+exports.isString = function(str) {
+ return str && typeof str === 'string';
+};
+
+/**
+ * Cast `val` to an array
+ * @return {Array}
+ */
+
+exports.arrayify = function(val) {
+ if (typeof val === 'string') return [val];
+ return val ? (Array.isArray(val) ? val : [val]) : [];
+};
+
+/**
+ * Get the last `n` element from the given `array`
+ * @param {Array} `array`
+ * @return {*}
+ */
+
+exports.last = function(arr, n) {
+ return arr[arr.length - (n || 1)];
+};