[ts] 排他联合类型问题?-灵析社区

interface IChildBase { points: number[]; } interface IChildLine extends IChildBase { type: 'line'; } interface IChildCircle extends IChildBase { type: 'circle'; } type ChildShape = IChildCircle | IChildLine; interface ITab { children: ChildShape[]; } // 用类型守卫来检查 children 的类型 function isLine(child: ChildShape): child is IChildLine { return child.type === 'line'; } function isCircle(child: ChildShape): child is IChildCircle { return child.type === 'circle'; } // 示例 const tab: ITab = { children: [ { type: 'circle', points: [1, 2, 3] }, { type: 'line', points: [4, 5] } ] }; tab.children.forEach(child => { if (isLine(child)) { console.log('This is a line.', child.points); } else if (isCircle(child)) { console.log('This is a circle.', child.points); } });