[Date Prev][Date Next][Thread Prev][Thread Next]
- Subject: Re: table insertion [was: Lua 5.1 (work2) now available]
- From: David Given <dg@...>
- Date: Thu, 4 Nov 2004 15:30:22 +0000
On Thursday 04 November 2004 15:08, Roberto Ierusalimschy wrote:
> I have a proposal for a new operator (after all these years): "*t" would
> return the "size" of table t. With that operator, the insertion of a new
> element in an array would be written as <<t[*t+1] = v>>. To remove the
> last element, we would write <<t[*t] = nil>>.
I quite like this, but I'm not keen on the new operator.
In a lot of ways, Lua's greatest strength (objects are tables) is also its
greatest weakness (tables are objects). It means that we can't use OO syntax
to manipulate tables. We can't use t.length to return the length of the table
because it conflicts with trying to fetch the 'length' field...
Currently, using a new operator is probably the best solution, because it
makes it clear that the operation is not calling a function (which a
pseudofunction like length(t) would not). But, is there a better way of
solving the underlying problem? Might it not be worth finally biting the
bullet and distinguishing between field lookups and method calls?
(BTW, would this work via a metatable operation? Could you virtualise it?)
+- David Given --McQ-+ (base 10) = (base pi)
| email@example.com | 1 = 1; 2 = 2; 3 = 3
| (firstname.lastname@example.org) | 3.1415926... = 10.0
+- www.cowlark.com --+ 4 = 12.201220211...