Re: Function as metatable (metafunctions?)

[Philipp Janda <siffiejoe@...>]

Am 31.03.2014 19:29 schröbte Javier Guerra Giraldez:
> On Mon, Mar 31, 2014 at 12:14 PM, Petite Abeille
> <petite.abeille@gmail.com> wrote:
> > local aFunction = function() end
> > debug.setmetatable( aFunction, { __tostring = function() return 'm e t a  f u n c t i o n' end } )
> > print( aFunction )
>
>
> ....
> local anotherFunction = function() .... end
> print (anotherFunction)
>
>
> so, you can't set metatable to _a_ function, you set the global
> function type's metatable

You could do

    local func_mt = setmetatable( {}, { __mode = "k" } )

    debug.setmetatable( function() end, {
      __tostring = function( f )
        return (func_mt[f] and func_mt[f].__tostring or rawtostring)( f )
      end,
      -- other metamethods ...
    } )

    local aFunction = function() end
    func_mt[ aFunction ] = { __tostring = function() return 'meta 
function' end } )

    print( aFunction )
    local anotherFunction = function() end
    print( anotherFunction )

Sadly we don't have `rawtostring` available in Lua, so this specific 
example is difficult, but in principle it should work ...

But I still have no idea what the OP really wants to do ...

Philipp