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// This demonstrates how conditional types work with unions
// In TypeScript, we'd have:
// type ToArray<T> = T extends any ? T[] : never;
// type ExtractString<T> = T extends string ? T : never;

// Examples demonstrating how conditional types work with unions
function createArray(item) {
  return Array.isArray(item) ? item : [item];
}

function extractString(item) {
  return typeof item === "string" ? item : null;
}

// ToArray examples
console.log("String to Array:", createArray("hello")); // ["hello"]
console.log("Number to Array:", createArray(42)); // [42]

// Using with union types (in JavaScript we'll just simulate)
const mixedArray = ["hello", 42, true, "world"];
console.log("Filtering strings from union:");

// Simulating ExtractString on a union type
const stringsOnly = mixedArray.filter(item => typeof item === "string");
console.log(stringsOnly); // ["hello", "world"]

// In TypeScript, this would be handled at compile time:
console.log('In TypeScript, the type "StringOrNumberArray" would be: string[] | number[]');
console.log('In TypeScript, the type "StringsOnly" would be: string | "hello"');

String to Array: [ 'hello' ]
Number to Array: [ 42 ]
Filtering strings from union:
[ 'hello', 'world' ]
In TypeScript, the type "StringOrNumberArray" would be: string[] | number[]
In TypeScript, the type "StringsOnly" would be: string | "hello"