# E0066

Warning name: `prefer_fixed_array`

Suggest `FixedArray` for mutated array literal.

This warning is emitted when an array literal is created and then mutated.
Consider using `FixedArray` to better express intent.

## Erroneous example

```{literalinclude} /sources/error_codes/0066_error/top.mbt
:language: moonbit
```

## Suggestion

Annotate the array literal as `FixedArray`:

```{literalinclude} /sources/error_codes/0066_fixed/top.mbt
:language: moonbit
```