# E4163

Local parameters are not local.

`#locals` is an attribute that aims to inline the given function parameter. This
error is raised when the given parameter is not a 'local' one.

## Erroneous example

```{literalinclude} /sources/error_codes/4163_error/top.mbt
:language: moonbit
```

## Suggestion

Apply `locals` to local functions only.

```{literalinclude} /sources/error_codes/4163_fixed/top.mbt
:language: moonbit
```