Re: Shorthand for appending to a table (was Re: 5.2 feature list?)

[David Jones <drj@...>]

On 12 Sep 2006, at 12:11, Tomas wrote:

> > Actually no-one was arguing it should go faster, merely that it  
> > should be easier to type.  There are two legitimate concerns as I  
> > see it:
> >
> > 1) when t is a long name.  Could be particularly embarrassing if  
> > you misspell it (personally I don't like long names, but hey)
> 	The problem is not with the operation, but with the name of the
> table.  If it bothers you why don't you simply change it to a short  
> one?
>
> > 2) when t is a more complex expression, eg: f(x)[#? + 1] = value.
> 	The problem here is not with the append operation also.  It shouldn't
> be clear/legible to separate the "more complex expression" into two  
> small
> and readable ones?  Something like: local t=f(x); t[#t+1]=value
> 	In both cases I think the discussion is diverging to a kind of
> competition of tastes: "I prefer this" X "I prefer that" :-(
>
> > I'm always very loath to suggest or support more syntax, but how  
> > about if '#' on its on in an expression inside [] were to mean the  
> > length of the table being indexed.  So you could go:
> >
> > t[#+1] = value
> >
> > It's pretty clear, and almost syntactically unambiguous.
> 	And one-character less (to use this subjective argument) than
> the current (and I think unquestionably legible, clear,  
> unambigous...):
>
> t[#t+1] = value

Well, the likes of you and me always use 1 character variable names,  
and we always introduce new variables for complex sub-expressions, so  
on the whole I'm inclined to agree with you.  But Lua already  
supports many style of programming, I was just recognising the needs  
of others.

Of course, if arrays were habitually indexed from 0 and the semantics  
of '#' changed accordingly then append would simply be:

t[#t] = value, and no-one would be complaining.

Personally, I don't like ':' as in a:b() to which your arguments also  
apply.

drj