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On 2017-01-25 04:21, Dirk Laurie wrote:
> It is an undocumented feature, though. The manual says:
> (The entry __name is used by some error-reporting functions.)
> tostring() is not an error-reporting function.
> Maybe the manual could merely say:
> (The entry __name is used by some reporting functions.)

It may also be a good idea to mention it in more places than just one
spot deep in the C API... or move the description elsewhere.

One solution:  At the end of §2.4 (Metatables and Metamethods), add
something roughly like:

= Because metatables are regular tables, they can contain arbitrary
= fields, not only the event names defined above. Some functions in
= the standard library (e.g., `tostring`) use other fields in metatables
= for their own purposes.
+ As an example, some functions use `__name` as a more specific type
+ name.  If present, it influences some error messages and the output
+ of `luaL_tolstring` and `tostring`.

(And the parenthetical remark on error messages at luaL_newmetatable can
be removed.)

(IIRC there were a bunch of other things you only get from the C API
sections.  Standalone interpreter-only users who don't "speak" C are
unlikely to read those as it's mostly incomprehensible gibberish for
them.  I had a list somewhere but can't find it right now. =/)

-- nobody