docs/reference/fidl/language/error-catalog/_fi-0181.md

## fi-0181: Library attribute argument references constant {:#fi-0181}

Attribute arguments on library declarations are not allowed to reference
constants:

{% include "docs/reference/fidl/language/error-catalog/label/_bad.md" %}

```fidl
{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/bad/fi-0181.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
```

Instead, provide a literal argument:

{% include "docs/reference/fidl/language/error-catalog/label/_good.md" %}

```fidl
{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/good/fi-0181.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
```

This restriction exists because it is rarely needed and supporting it adds
unwarranted complexity to the compiler.