# E0040

Warning name: `multiline_string_escape`

Escape sequences in `$|` multiline string lines are deprecated.

MoonBit treats `$|` lines as multiline string content. Escape sequences such as
`\n`, `\t`, and `\\` in those lines are deprecated because they will be treated
literally in the future.

## Erroneous example

```{literalinclude} /sources/error_codes/0040_error/top.mbt
:language: moonbit
```

## Suggestion

Use interpolation when you need an escaped character, or write the literal text
directly when that is what the string should contain.

```{literalinclude} /sources/error_codes/0040_fixed/top.mbt
:language: moonbit
```