Move internal modules to “internal” folder.

.internal/createBind.js

@@ -0,0 +1,28 @@
+import createCtor from './.internal/createCtor.js';
+import root from './.internal/root.js';
+
+/** Used to compose bitmasks for function metadata. */
+const WRAP_BIND_FLAG = 1;
+
+/**
+ * Creates a function that wraps `func` to invoke it with the optional `this`
+ * binding of `thisArg`.
+ *
+ * @private
+ * @param {Function} func The function to wrap.
+ * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
+ * @param {*} [thisArg] The `this` binding of `func`.
+ * @returns {Function} Returns the new wrapped function.
+ */
+function createBind(func, bitmask, thisArg) {
+  const isBind = bitmask & WRAP_BIND_FLAG;
+  const Ctor = createCtor(func);
+
+  function wrapper(...args) {
+    const fn = (this && this !== root && this instanceof wrapper) ? Ctor : func;
+    return fn.apply(isBind ? thisArg : this, args);
+  }
+  return wrapper;
+}
+
+export default createBind;