Re: Nil and false in Lua design

[Carsten Fuchs <carsten.fuchs@...>]

Am 14.10.2013 09:22, schrieb Dirk Laurie:
> 2013/10/14 steve donovan <steve.j.donovan@gmail.com>:
>
> > Except that there are hundreds of thousands of lines out there that do
> > 'if val' assuming that nil evaluates to false. There's really only two
> > cases - it's not like C./Python where you have to consider zero as
> > well.  And languages which think that '' is false rightly deserve our
> > scorn.
>
> Python considers empty lists, tuples and dicts to be false too, and
> in general seems to have a false element in almostt every type.
> It's one of those things that divide people into lovers and haters.

How about a metamethod __tobool ?

Then everyone could define him- or herself if and how any Lua type 
should evaluate to bool in a boolean expression.  :-)

Best regards,
Carsten


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