Function throttle

throttle<T extends (...args: unknown[]) => unknown>(
fn: T,
limit: number,
): (...args: Parameters<T>) => void
节流函数——在 limit 毫秒内最多执行一次
Type Parameters
- T extends (...args: unknown[]) => unknown
Parameters
- fn: T
  待节流的原始函数
- limit: number
  节流间隔毫秒数
Returns (...args: Parameters<T>) => void
经过节流封装的函数，与 fn 具有相同入参
Example
```
const handleScroll = throttle(() => updateHeader(), 100)
```
- Defined in async.ts:47