Re: [ANN] Updated uFAQ (Unofficial Lua FAQ)

[David Kastrup <dak@...>]

Dirk Laurie <dpl@sun.ac.za> writes:

> On Tue, Aug 30, 2011 at 09:00:15AM +0200, steve donovan wrote:
>> On Tue, Aug 30, 2011 at 8:30 AM, Axel Kittenberger <axkibe@gmail.com> wrote:
>> > 1.5.1 Why do Lua arrays count from one not zero?
>> > The answer does not answer the question. Why?
>> 
>> That's a good point. In my experience engineers and scientists (who
>> have been infected with the Excel virus and hack with VBA) don't get
>> arrays starting at zero. And they can't read curly-brace languages
>> either.
>
> Because *people* count from one, not zero.

The starting point for _counting_ is zero (the state before counting the
first element).  The starting point for _numbering_ is one.

> A harder question would be "why do arrays in some other languages count 
> from zero not one?"  The answer for C is a good one: "so that *(A+k) and 
> A[k] mean the same".

In a language not having dynamically sized multidimensional arrays, the
index arithmetic for simulating them manually is much more pleasant when
arrays are zero-based.

In many cases where the phrase "index arithmetic" applies, zero-based
indexing leads to more straightforward expressions.

-- 
David Kastrup