@andranik-arakelyan/js-utilities/dist/lib/generator/range.d.ts

Javascript utilities

/**
 * Generates a sequence of numbers from start to stop (exclusive) with an optional step.
 * This is a JavaScript implementation of Python's range() function using generators.
 * Returns an iterator that yields numbers on demand without creating an array in memory.
 *
 * @param start The starting value of the sequence
 * @param stop The ending value of the sequence (exclusive)
 * @param step The step between values (defaults to 1)
 * @returns A generator that yields numbers in the specified range
 *
 * @throws {Error} When step is 0
 *
 * @example
 * // Basic usage - range(stop)
 * [...range(5)]; // [0, 1, 2, 3, 4]
 *
 * @example
 * // With start and stop - range(start, stop)
 * [...range(2, 8)]; // [2, 3, 4, 5, 6, 7]
 *
 * @example
 * // With step - range(start, stop, step)
 * [...range(0, 10, 2)]; // [0, 2, 4, 6, 8]
 * [...range(10, 0, -2)]; // [10, 8, 6, 4, 2]
 *
 * @example
 * // Using with for...of loop (memory efficient)
 * for (const i of range(1000000)) {
 *   if (i > 5) break;
 *   console.log(i); // 0, 1, 2, 3, 4, 5
 * }
 *
 * @example
 * // Negative ranges
 * [...range(-5, -1)]; // [-5, -4, -3, -2]
 * [...range(-1, -5, -1)]; // [-1, -2, -3, -4]
 *
 * @example
 * // Empty ranges
 * [...range(5, 5)]; // []
 * [...range(5, 0)]; // []
 * [...range(0, 5, -1)]; // []
 */
export declare function range(start: number, stop?: number, step?: number): Generator<number, void, unknown>;
/**
 * Creates a range iterator that can be used multiple times.
 * Unlike the generator function, this returns an iterable object
 * that can be iterated over multiple times.
 *
 * @param start The starting value of the sequence
 * @param stop The ending value of the sequence (exclusive)
 * @param step The step between values (defaults to 1)
 * @returns An iterable object that can be used with for...of loops multiple times
 *
 * @example
 * const r = rangeIterable(0, 5);
 * [...r]; // [0, 1, 2, 3, 4]
 * [...r]; // [0, 1, 2, 3, 4] - can be used again
 */
export declare function rangeIterable(start: number, stop?: number, step?: number): Iterable<number>;