Function flatten

packages/common/decorators/core/dependencies.decorator.ts:3–10

(
  arr: T,
)

import { PARAMTYPES_METADATA } from '../../constants';

export function flatten<T extends Array<unknown> = any>(
  arr: T,
): T extends Array<infer R> ? R : never {
  const flat = ([] as any[]).concat(...arr);
  return flat.some(Array.isArray)
    ? flatten(flat)
    : (flat as T extends Array<infer R> ? R : never);
}

/**
 * Decorator that sets required dependencies (required with a vanilla JavaScript objects)