Re: Syntactical ugliness - does it matter?

[Sean Conner <sean@...>]

It was thus said that the Great Dibyendu Majumdar once stated:
> On Tue, 4 Jun 2019 at 21:24, Sean Conner <sean@conman.org> wrote:
> >
> > It was thus said that the Great Dibyendu Majumdar once stated:
> > >
> > > But more interestingly suppose you have a user defined type where the
> > > metatable has been registered. Suppose that the name under which you
> > > have registered the metatable is 'Torch.Tensor'.
> > >
> > > Then you can write:
> > >
> > > local x: Torch.Tensor = ...
> > > function Foo (x: Torch.Tensor)
> > > end
> >
> >   Interesting.  Can you handle the case where the user defined type has more
> > than just letters, digits and periods?  I ask because I also use colons in
> > my user defined types,  such as:
> >
> >         org.conman.net:addr
> >         org.conman.net:sock
> >
> 
> At the moment, no. Each period separated component must be a Name -
> i.e. Lua identifier. So digits can appear within a name as per Lua
> rules. But ':' is problematic as I allow cast operations such as:
> 
> local v = @Torch.Tensor SomeFuncReturningTensor()
> 
> You can imagine that ':' here would cause a problem - i.e. should it
> be interpreted as a self operator?
> 
> The chosen syntax is easy to handle with Lua's existing lexer and
> parser with some minor enhancements.

  This even breaks with standard Lua, because of the following metatypes:

	FILE*		defined by the Lua io module
	lpeg-pattern	defined by LPEG

  I suppose you could do:

	local v = @['FILE*'] SomeFuncReturningFileObject()

given that foo.bar is syntactic surgar for foo['bar'].  

  -spc (Just a thought ...  )