# E0042

Warning name: `invalid_attribute`

Invalid attribute.

This warning will be emitted when the program contain attribute unrecognized by MoonBit,
or the syntax of attribute has incorrect shape.

## Erroneous example
```{literalinclude} /sources/error_codes/0042_error/top.mbt
:language: moonbit
```

## Suggestion
Check if there is typo in the attribute declaration, and check the document of the attribute for the arguments it accept.
If you intend to write a attribute for use by foreign tools,
make sure the attribute's name is `#xxx.yyy`, such as `#coverage.skip`,
so that MoonBit will treat it as a foreign attribute and ignore it.