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index.js

@@ -19,6 +19,7 @@ const wrapPath = require("@validatem/wrap-path");
 // FIXME: Prevent prototype pollution
 // FIXME: Figure out an ergonomic way to do nested array merging (ie. flattening)
 // FIXME: Figure out a better way to pass around the options, that doesn't 'leak' to custom functions
+// TODO: Add an option for removing deleted keys (rather than just setting them to `undefined`)
 
 // FIXME: Make sure to explain the purpose of this in the documentation (multi-step merging, like in zapdb)
 let DeleteValue = Symbol("DeleteValue");
@@ -128,6 +129,12 @@ function mergeValue(rule, a, b, path, options) {
 
 module.exports = {
 	DeleteValue: DeleteValue, // FIXME: Test this
+	Recursive: function (mergeFunc) {
+		return {
+			__mergeByTemplateOperation: "recursive",
+			mergeFunc: mergeFunc
+		};
+	},
 	createMerger: function createMerger(_template, _options) {
 		let [ template, options ] = validateArguments(arguments, {
 			template: [],