The function datatype specs lacks of attributes

[GiuseppeChillemi]

I have found that parse-func-spec in code has this following rule defined:

attr-val=: ['catch | 'throw | 'trace | 'no-trace]

But they are not documented in function! datatype specification.

https://github.com/red/docs/blob/master/en/datatypes/function.adoc

It seems an oversight, discussion here