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- Subject: Re: strange table index "end"
- From: Sean Conner <sean@...>
- Date: Wed, 9 Mar 2011 15:26:26 -0500
It was thus said that the Great Axel Kittenberger once stated:
> > Implementing this in a hand-written parser such as the one used by Lua is
> > left as an exercise for the reader :-)
> Keywords as table indexes aren't difficult, its just some extra code that:
> o when the parser is in a place it expects a table index
> oo that is after a dot.
> o it turns the keyword back into it original string meaning.
> But it is extra code, for most projects, we'd just go away, but Lua
> takes lot of care on its memory footprint and covering uncommon cases.
> When local variables are allowed to be identical to keywords as well,
> then the parser suddenly gets a magnitude more complex!
> locel end = 1
> if foocondition then end = end + 1 end
> Also gets the parser in our heads much more confused!
> I still guess there wouldn't be ambigous situations, though, for a
> parser with infinitely long lookahead.
A very pathological case:
if if == then then then = else else else = end end
-spc (Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo )