more work

node_modules/lodash/lang/isNative.js

@@ -0,0 +1,54 @@
+var escapeRegExp = require('../string/escapeRegExp'),
+    isObjectLike = require('../internal/isObjectLike');
+
+/** `Object#toString` result references. */
+var funcTag = '[object Function]';
+
+/** Used to detect host constructors (Safari > 5). */
+var reIsHostCtor = /^\[object .+?Constructor\]$/;
+
+/** Used for native method references. */
+var objectProto = Object.prototype;
+
+/** Used to resolve the decompiled source of functions. */
+var fnToString = Function.prototype.toString;
+
+/**
+ * Used to resolve the [`toStringTag`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.prototype.tostring)
+ * of values.
+ */
+var objToString = objectProto.toString;
+
+/** Used to detect if a method is native. */
+var reIsNative = RegExp('^' +
+  escapeRegExp(objToString)
+  .replace(/toString|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
+);
+
+/**
+ * Checks if `value` is a native function.
+ *
+ * @static
+ * @memberOf _
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a native function, else `false`.
+ * @example
+ *
+ * _.isNative(Array.prototype.push);
+ * // => true
+ *
+ * _.isNative(_);
+ * // => false
+ */
+function isNative(value) {
+  if (value == null) {
+    return false;
+  }
+  if (objToString.call(value) == funcTag) {
+    return reIsNative.test(fnToString.call(value));
+  }
+  return isObjectLike(value) && reIsHostCtor.test(value);
+}
+
+module.exports = isNative;