# Nested functions are not supported Rule ``arkts-no-nested-funcs`` **Severity: error** ArkTS does not support nested functions. Use lambdas instead. ## TypeScript ``` function addNum(a: number, b: number): void { // nested function: function logToConsole(message: String): void { console.log(message) } let result = a + b // Invoking the nested function: logToConsole("result is " + result) } ``` ## ArkTS ``` function addNum(a: number, b: number): void { // Use lambda instead of a nested function: let logToConsole: (message: string) => void = (message: string): void => { console.log(message) } let result = a + b logToConsole("result is " + result) } ```