| 14901 | } |
| 14902 | |
| 14903 | function genFor( |
| 14904 | el, //虚拟dom 节点 |
| 14905 | state, //状态 |
| 14906 | altGen, //函数不知道是什么 |
| 14907 | altHelper //函数不知道是什么 |
| 14908 | ) { |
| 14909 | |
| 14910 | var exp = el.for; //含有for的标签 |
| 14911 | var alias = el.alias; //"item" |
| 14912 | var iterator1 = el.iterator1 ? ("," + (el.iterator1)) : ''; //iterator1 "index" 索引 |
| 14913 | var iterator2 = el.iterator2 ? ("," + (el.iterator2)) : ''; //iterator2: "key" |
| 14914 | |
| 14915 | if ("development" !== 'production' && |
| 14916 | state.maybeComponent(el) && |
| 14917 | el.tag !== 'slot' && |
| 14918 | el.tag !== 'template' && !el.key |
| 14919 | ) { |
| 14920 | state.warn( |
| 14921 | "<" + (el.tag) + " v-for=\"" + alias + " in " + exp + "\">: component lists rendered with " + |
| 14922 | "v-for should have explicit keys. " + |
| 14923 | "See https://vuejs.org/guide/list.html#key for more info.", |
| 14924 | true /* tip */ |
| 14925 | ); |
| 14926 | } |
| 14927 | |
| 14928 | el.forProcessed = true; // avoid recursion 标记已经处理过for |
| 14929 | //递归回调 |
| 14930 | return (altHelper || '_l') + "((" + exp + ")," + |
| 14931 | "function(" + alias + iterator1 + iterator2 + "){" + |
| 14932 | "return " + ((altGen || genElement)(el, state)) + |
| 14933 | '})' |
| 14934 | } |
| 14935 | |
| 14936 | //根据判断el是否含有 指令属性,key,ref，refInFor，v-for,pre,component |
| 14937 | function genData$2(el, state) { |