判断索引所在括号层级

代码实现

1. JavaScript

function isInBracket(index: number, bracketRange: number[][][], startLevel = 0, endLevel = startLevel) {
	/** 目标索引要存在于startLevel,但不存在于endLevel+1 */
	let startFlag, endPlusOneFlag: boolean
	startFlag = false
	if (startLevel == 0) startFlag = true
	else if (startLevel - 1 < bracketRange.length) {
			for (const range of bracketRange[startLevel - 1]) {
					if (index >= range[0] && index <= range[1]) {
							startFlag = true; break;
					}
			}
	}
	endPlusOneFlag = false
	if (endLevel < bracketRange.length) {
			for (const range of bracketRange[endLevel]) {
					if (index >= range[0] && index <= range[1]) {
							endPlusOneFlag = true; break
					}
			}
	}
	return startFlag && !endPlusOneFlag
}