docs/reference/fidl/language/error-catalog/_fi-0075.md

## fi-0075: Invalid primitive used for method payload {:#fi-0075}

Primitives cannot be used as method method payload:

{% 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-0075.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
```

Use a type of the `struct`, `table`, or `union` layout instead:

{% 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-0075.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
```

For cases where the desirable payload really is just a primitive value, and
future evolution is not a concern, wrapping the value in a `struct` layout will
result in a payload that is the same size as desired value is by itself.