# curly_braces_in_flow_control_structures

> Details about the curly_braces_in_flow_control_structures diagnostic produced by the Dart analyzer.



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_Statements in {0} should be enclosed in a block._

## Description

The analyzer produces this diagnostic when a control structure (`if`,
`for`, `while`, or `do` statement) has a statement other than a block.

## Example

The following code produces this diagnostic because the `then` statement
is not enclosed in a block:

```dart
int f(bool b) {
  if (b)
    [!return 1;!]
  return 0;
}
```

## Common fixes

Add braces around the statement that should be a block:

```dart
int f(bool b) {
  if (b) {
    return 1;
  }
  return 0;
}
```

