Bytlinux

 In TypeScript, you can use an array to represent a closed list of strings by specifying the valid string values as elements of the array. Here's how you can create and use such an array: ```typescript const validColors: string[] = ["red", "green", "blue"]; function getColorName(color: string): string {   if (validColors.includes(color)) {     return color;   } else {     throw new Error("Invalid color");   } } // Example usage: try {   const selectedColor = "red";   const validColor = getColorName(selectedColor);   console.log(`Selected color: ${validColor}`); } catch (error) {   console.error(error.message); } ``` In this example: 1. `validColors` is an array that contains a list of valid color strings: "red", "green", and "blue". 2. The `getColorName` function takes a string argument, checks if it exists in the `validColors` array using `includes`, and returns the same string if it's valid. If th

 To ensure that all keys of an enum are present in an array in TypeScript, you can use TypeScript's type system to perform a type check. Here's an example of how to achieve this: Suppose you have an enum like this: ```typescript enum Days {   Monday,   Tuesday,   Wednesday,   Thursday,   Friday,   Saturday,   Sunday } ``` And you want to ensure that all enum keys are present in an array. You can define a type that enforces this check: ```typescript type AllEnumKeysInArray<T> = {   [K in keyof T]: K; }; function ensureAllEnumKeysInArray<T>(enumType: T, keysArray: (keyof T)[]): keysArray is (keyof T)[] {   const enumKeys = Object.keys(enumType).filter(key => isNaN(Number(key))) as (keyof T)[];   return enumKeys.every(key => keysArray.includes(key)); } // Usage const daysArray: (keyof typeof Days)[] = [Days.Monday, Days.Tuesday, Days.Wednesday, Days.Thursday, Days.Friday, Days.Saturday, Days.Sunday]; if (ensureAllEnumKeysInArray(Days, daysArray)) {   console.log(