# unnecessary_string_interpolations

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



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_Unnecessary use of string interpolation._

## Description

The analyzer produces this diagnostic when a string literal contains a
single interpolation of a `String`-valued variable and no other
characters.

## Example

The following code produces this diagnostic because the string literal
contains a single interpolation and doesn't contain any character outside
the interpolation:

```dart
String f(String s) => [!'$s'!];
```

## Common fixes

Replace the string literal with the content of the interpolation:

```dart
String f(String s) => s;
```

