# E3011

The assignment contains an invalid left-hand-side (LHS) expression,
such as a constant or a constructor.

## Erroneous example

```{literalinclude} /sources/error_codes/3011_error/top.mbt
:language: moonbit
```

## Suggestion

Change the LHS to a valid mutable memory location,
such as a mutable variable or a mutable field:

```{literalinclude} /sources/error_codes/3011_fixed/top.mbt
:language: moonbit
```