/**
* Type-safe array helper functions for accessing array elements
* with compile-time guarantees when used with noUncheckedIndexedAccess.
*/
/**
* Get the first element of an array with compile-time guarantee it exists.
* @param arr - The array to get the first element from
* @param context - Optional context for error message (e.g., "Creating master widget")
* @throws Error if array is empty
* @returns The first element of the array
*/
export function first<T>(arr: readonly T[], context?: string): T {
if (arr.length === 0) {
throw new Error(context ? `${context}: Array is empty` : 'Array is empty')
}
return arr[0] as T // Safe: length check above
}
/**
* Type guard for non-empty arrays.
* When this returns true, TypeScript knows the array has at least one element.
* @param arr - The array to check
* @returns True if the array is non-empty
*
* @example
* ```typescript
* if (isNonEmpty(results)) {
* // TypeScript knows results[0] is T, not T | undefined
* const firstResult = results[0]
* }
* ```
*/
export function isNonEmpty<T>(arr: readonly T[]): arr is readonly [T, ...T[]] {
return arr.length > 0
}
