Move internal modules to “internal” folder.

.internal/createRecurry.js

@@ -0,0 +1,56 @@
+import isLaziable from './.internal/isLaziable.js';
+import setData from './.internal/setData.js';
+import setWrapToString from './.internal/setWrapToString.js';
+
+/** Used to compose bitmasks for function metadata. */
+const WRAP_BIND_FLAG = 1;
+const WRAP_BIND_KEY_FLAG = 2;
+const WRAP_CURRY_BOUND_FLAG = 4;
+const WRAP_CURRY_FLAG = 8;
+const WRAP_PARTIAL_FLAG = 32;
+const WRAP_PARTIAL_RIGHT_FLAG = 64;
+
+/**
+ * Creates a function that wraps `func` to continue currying.
+ *
+ * @private
+ * @param {Function} func The function to wrap.
+ * @param {number} bitmask The bitmask flags. See `createWrap` for more details.
+ * @param {Function} wrapFunc The function to create the `func` wrapper.
+ * @param {*} placeholder The placeholder value.
+ * @param {*} [thisArg] The `this` binding of `func`.
+ * @param {Array} [partials] The arguments to prepend to those provided to
+ *  the new function.
+ * @param {Array} [holders] The `partials` placeholder indexes.
+ * @param {Array} [argPos] The argument positions of the new function.
+ * @param {number} [ary] The arity cap of `func`.
+ * @param {number} [arity] The arity of `func`.
+ * @returns {Function} Returns the new wrapped function.
+ */
+function createRecurry(func, bitmask, wrapFunc, placeholder, thisArg, partials, holders, argPos, ary, arity) {
+  const isCurry = bitmask & WRAP_CURRY_FLAG;
+  const newHolders = isCurry ? holders : undefined;
+  const newHoldersRight = isCurry ? undefined : holders;
+  const newPartials = isCurry ? partials : undefined;
+  const newPartialsRight = isCurry ? undefined : partials;
+
+  bitmask |= (isCurry ? WRAP_PARTIAL_FLAG : WRAP_PARTIAL_RIGHT_FLAG);
+  bitmask &= ~(isCurry ? WRAP_PARTIAL_RIGHT_FLAG : WRAP_PARTIAL_FLAG);
+
+  if (!(bitmask & WRAP_CURRY_BOUND_FLAG)) {
+    bitmask &= ~(WRAP_BIND_FLAG | WRAP_BIND_KEY_FLAG);
+  }
+  const newData = [
+    func, bitmask, thisArg, newPartials, newHolders, newPartialsRight,
+    newHoldersRight, argPos, ary, arity
+  ];
+
+  const result = wrapFunc(...newData);
+  if (isLaziable(func)) {
+    setData(result, newData);
+  }
+  result.placeholder = placeholder;
+  return setWrapToString(result, func, bitmask);
+}
+
+export default createRecurry;