# 錯誤紀錄
### vscode出現小蚯蚓,然後顯示`control-flow-collections`相關錯誤
Ans :
1) Keep the analysis_options.yaml in your root folder with this code:
```yaml
analyzer:
enable-experiment:
- control-flow-collections
```
2) Don't use brackets {} in between your for loops Ex:
```java
<Widget>[
for (final category in categories)
CategoryWidget(category: category)
],
```
3) Important step which is probably why it's not working for you: Change your Dart version constraint in the pubspec.yml file in your root folder to 2.5.2
```yaml
environment:
sdk: ">=2.5.2 <3.0.0"
```
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