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docs(regex): fix es2022 indices

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xt1995726 2022-06-30 20:31:26 +08:00
parent f6bb1b931d
commit f45f032a23
1 changed files with 6 additions and 6 deletions
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docs/regex.md
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@ -633,11 +633,11 @@ RE_TWICE.test('abc!abc!ab') // false
正则匹配的结果，在原始字符串里面的开始位置和结束位置，目前获取并不是很方便。正则实例的`exec()`方法的返回结果，现有一个`index`属性，可以获取整个匹配结果的开始位置。但是，组匹配的每个组的开始位置，很难拿到。 正则匹配的结果，在原始字符串里面的开始位置和结束位置，目前获取并不是很方便。正则实例的`exec()`方法的返回结果，现有一个`index`属性，可以获取整个匹配结果的开始位置。但是，组匹配的每个组的开始位置，很难拿到。
[ES2022](https://github.com/tc39/proposal-regexp-match-Indices) 为`exec()`方法的返回结果加上`indices`属性，在这个属性上面可以拿到匹配的开始位置和结束位置。 [ES2022](https://github.com/tc39/proposal-regexp-match-Indices) 中新增`d`修饰符，使用`/d`修饰符，为`exec()`、`match`等方法的返回结果加上`indices`属性，在这个属性上面可以拿到匹配的开始位置和结束位置。
```javascript ```javascript
const text = 'zabbcdef'; const text = 'zabbcdef';
const re = /ab/; const re = /ab/d;
const result = re.exec(text); const result = re.exec(text);
result.index // 1 result.index // 1
@ -652,7 +652,7 @@ result.indices // [ [1, 3] ]
```javascript ```javascript
const text = 'zabbcdef'; const text = 'zabbcdef';
const re = /ab+(cd)/; const re = /ab+(cd)/d;
const result = re.exec(text); const result = re.exec(text);
result.indices // [ [ 1, 6 ], [ 4, 6 ] ] result.indices // [ [ 1, 6 ], [ 4, 6 ] ]
@ -664,7 +664,7 @@ result.indices // [ [ 1, 6 ], [ 4, 6 ] ]
```javascript ```javascript
const text = 'zabbcdef'; const text = 'zabbcdef';
const re = /ab+(cd(ef))/; const re = /ab+(cd(ef))/d;
const result = re.exec(text); const result = re.exec(text);
result.indices // [ [1, 8], [4, 8], [6, 8] ] result.indices // [ [1, 8], [4, 8], [6, 8] ]
@ -676,7 +676,7 @@ result.indices // [ [1, 8], [4, 8], [6, 8] ]
```javascript ```javascript
const text = 'zabbcdef'; const text = 'zabbcdef';
const re = /ab+(?<Z>cd)/; const re = /ab+(?<Z>cd)/d;
const result = re.exec(text); const result = re.exec(text);
result.indices.groups // { Z: [ 4, 6 ] } result.indices.groups // { Z: [ 4, 6 ] }
@ -688,7 +688,7 @@ result.indices.groups // { Z: [ 4, 6 ] }
```javascript ```javascript
const text = 'zabbcdef'; const text = 'zabbcdef';
const re = /ab+(?<Z>ce)?/; const re = /ab+(?<Z>ce)?/d;
const result = re.exec(text); const result = re.exec(text);
result.indices[1] // undefined result.indices[1] // undefined