# util > A Node.js-compatible implementation of the core `util` module - Source: https://titaniumsdk.com/docs/sdk/13.0.1/util - Titanium SDK version: 13.0.1 - Kind: pseudo - Platforms: Android, iPhone, iPad, macOS - Since: Titanium SDK 8.1.0 Titanium provides a number of shims and ports of core Node.js module functionality. This module is intended to provide a Node-compatible port of the `util` core module. More details on the Node.js API can be found in their [util module documentation](https://nodejs.org/api/util.html) ## Properties ### types - Type: util.types - Platforms: Android, iPhone, iPad, macOS `util.types` provides type checks for different kinds of built-in objects. Unlike `instanceof` or `Object.prototype.toString.call(value)`, these checks do not inspect properties of the object that are accessible from JavaScript (like their prototype), and usually have the overhead of calling into C++. The result generally does not make any guarantees about what kinds of properties or behavior a value exposes in JavaScript. They are primarily useful for addon developers who prefer to do type checking in JavaScript. ## Methods ### callbackify - Platforms: Android, iPhone, iPad, macOS Takes an `async` function (or a function that returns a `Promise`) and returns a function following the error-first callback style, i.e. taking an `(err, value) => ... callback` as the last argument. In the callback, the first argument will be the rejection reason (or `null` if the `Promise` resolved), and the second argument will be the resolved value. Parameters: - `original` (Function): An `async` function Returns: Function - a callback style function ### debug - Platforms: Android, iPhone, iPad, macOS Alias for `util.debuglog`. Usage allows for readability of that doesn't imply logging when only using `util.debuglog().enabled`. Parameters: - `section` (String): A string identifying the portion of the application for which the `debuglog` function is being created. - `callback` (Function, optional): A callback invoked the first time the logging function is called with a function argument that is a more optimized logging function. Returns: Function - The logging function ### debuglog - Platforms: Android, iPhone, iPad, macOS The `util.debuglog()` method is used to create a function that conditionally writes debug messages to `stderr` based on the existence of the `NODE_DEBUG` environment variable. If the section name appears within the value of that environment variable, then the returned function operates similar to `console.error()`. If not, then the returned function is a no-op. **NOTE:** Titanium currently returns a no-op regardless of the `NODE_DEBUG` environment variable. Parameters: - `section` (String): A string identifying the portion of the application for which the `debuglog` function is being created. - `callback` (Function, optional): A callback invoked the first time the logging function is called with a function argument that is a more optimized logging function. Returns: Function - The logging function ### deprecate - Platforms: Android, iPhone, iPad, macOS The `util.deprecate()` method wraps fn (which may be a function or class) in such a way that it is marked as deprecated. Parameters: - `fn` (Function): The function that is being deprecated. - `msg` (String): A warning message to display when the deprecated function is invoked. - `code` (String, optional): A deprecation code. **NOTE:** Titanium currently ignores this argument. Returns: Function - The deprecated function wrapped to emit a warning. ### format - Platforms: Android, iPhone, iPad, macOS The `util.format()` method returns a formatted string using the first argument as a printf-like format string which can contain zero or more format specifiers. Each specifier is replaced with the converted value from the corresponding argument. Parameters: - `format` (String): A `printf`-like format string. - `args` (any, optional, repeatable): variable arguments to inject into the formatted string ### formatWithOptions - Platforms: Android, iPhone, iPad, macOS This function is identical to `util.format()`, except in that it takes an `inspectOptions` argument which specifies options that are passed along to `util.inspect()`. Parameters: - `inspectOptions` (UtilInspectOptions): Options passed along to [util.inspect](https://titaniumsdk.com/docs/sdk/util.md#inspect)`()` - `format` (String): A `printf`-like format string. ### inherits - Platforms: Android, iPhone, iPad, macOS Usage of `util.inherits()` is discouraged. Please use the ES6 `class` and `extends` keywords to get language level inheritance support. Also note that the two styles are semantically incompatible. Inherit the prototype methods from one constructor into another. The prototype of `constructor` will be set to a new object created from `superConstructor`. This mainly adds some input validation on top of `Object.setPrototypeOf(constructor.prototype, superConstructor.prototype)`. As an additional convenience, `superConstructor` will be accessible through the `constructor.super_` property. Parameters: - `constructor` (Function): constructor function for "subclass" - `superConstructor` (Function): constructor function for "super class" ### inspect - Platforms: Android, iPhone, iPad, macOS The `util.inspect()` method returns a string representation of `object` that is intended for debugging. The output of `util.inspect` may change at any time and should not be depended upon programmatically. Additional `options` may be passed that alter the result. `util.inspect()` will use the constructor's name and/or `@@toStringTag` to make an identifiable tag for an inspected `value`. Parameters: - `object` (any): Any JavaScript primitive or Object. - `options` (UtilInspectOptions, optional): Additional options to modify the output of the inspect function Returns: String ### isArray - Platforms: Android, iPhone, iPad, macOS Alias for `Array.isArray()`. Returns `true` if the given `object` is an `Array`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isBoolean - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `Boolean`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isBuffer - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `Buffer`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isDate - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `Date`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isError - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is an `Error`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isFunction - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `Function`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isNull - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is strictly `null`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isNullOrUndefined - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is `null` or `undefined`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isNumber - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `Number`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isObject - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is strictly an `Object` **and** not a `Function` (even though functions are objects in JavaScript). Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isPrimitive - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a primitive type. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isRegExp - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `RegExp`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isString - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `string`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isSymbol - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is a `Symbol`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### isUndefined - Platforms: Android, iPhone, iPad, macOS Returns `true` if the given `object` is `undefined`. Otherwise, returns `false`. Parameters: - `object` (any): any value Returns: Boolean ### log - Platforms: Android, iPhone, iPad, macOS The `util.log()` method prints the given `string` to `stdout` with an included timestamp. Parameters: - `string` (String): string to print ### promisify - Platforms: Android, iPhone, iPad, macOS Takes a function following the common error-first callback style, i.e. taking an `(err, value) => ... callback` as the last argument, and returns a version that returns promises. Parameters: - `original` (Function): A typical Node.js style callback function Returns: Function - a function that returns a `Promise` --- - This corpus documents Titanium SDK 13.4.1. Anything here that does not name a version describes 13.4.1. - Titanium is maintained by TiDev. The Appcelerator toolchain is retired: there is no `appc` CLI, no Appcelerator Studio and no hosted build service. The supported CLI is `titanium` on npm, invoked as `ti`.