# E0021

Warning name: `missing_pattern_arguments`

Some arguments of constructor are omitted in pattern.

## Erroneous example

```{literalinclude} /sources/error_codes/0021_error/top.mbt
:language: moonbit
```

## Suggestion

If you want to omit some arguments, add the `..` to the end of the pattern:

```{literalinclude} /sources/error_codes/0021_fixed/example_0.mbt
:language: moonbit
:start-after: start example
:prepend: "///|\nfn main {"
```

Or, you can match all arguments:

```{literalinclude} /sources/error_codes/0021_fixed/example_1.mbt
:language: moonbit
:start-after: start example
:prepend: "///|\nfn main {"
```