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Re: Notice of intent to freeze RFCs 204, 206, and revise 207

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Jeremy Howard
September 20, 2000 14:29
Re: Notice of intent to freeze RFCs 204, 206, and revise 207
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Buddha Buck wrote:
> On RFC 204 (LOL refs as indices), I have followed the discussion from
> Ilya that list references will have problems when objects that used
> blessed references to lists as their internal representation are used
> as indices.  This does indeed seem to be a problem, but I'm uncertain
> how big of a problem.
> Would it help if the RFC stated that the index had to be either a
> scalar integer or an ARRAY ref of integers?  Since objects would be
> blessed as something other than ARRAY, they would need to be converted
> first.  If it was an object, it would try to call standard methods to
> convert to a scalar integer, a list of integers, or an ARRAY ref of
> integers.  Just an idea.
There are two options to resolve any potential ambiguity:

 1. Require that LOLs as indexes be unblessed, or
 2. Define interface precedence to resolve ambiguity

(1) is obvious. (2) is simply a case of defining precedence such as:
"If a scalar used as an array index overloads operators such that it has
both a LOL interface, and a integer interface, it is treated as an LOL for
the purpose of array indexing"

I prefer (2), because an object with an LOL interface should act just like
an LOL, and work anywhere an LOL works.
> On RFC 207 (efficient array loops), based on discusion and additional
> thought on my part, I want to clarify and change the syntax used in the
> RFC.  I also want to go into more detail about how the scope of the
> efficient array loops is derived.
I agree with all of your proposed changes. Also, incorporate the rules that
define the width of the implied loop, that you included in an earlier email
to the list.

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