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[REBOL] Re: R: Re: Correct Behaviour? Was False = 2 ????

From: robbo1mark:aol at: 3-Jul-2001 6:06

Everybody, Interesting to note peoples points and reasonings on this thread & for what it's worth I think they all have some validity. Regards Indexing starting at Zero, I have mixed views on this and still haven't firmly decided which side of the fence I fall on although I think I lean towards the zero position. For instance 'HEAD is always index 1 whereas 'TAIL is always ( index? last + 1 ), I see 'TAIL as being correct because it is the position after the last element of a series! If you accept that as true then surely 'HEAD of a series! should be index position zero, agreed? In my view this should be the "correct" behaviour
>> index? head [a b c]
== 0 My Reasoning being 'INSERT joins values to the head of a series! "before" the first element. With regards to me "giving" 'PICK the ability to accept NONE as an index position, this was only done for example purposes to highlight a further inconsistency in REBOL. The Conditional Functions like 'IF & 'EITHER accept NONE as the logical equivalent of 'FALSE.
>> either none [ true ] [ false ]
== false Therefore if you can do this....
>> pick [true false] false
== false
>> pick [true false] true
== true Then why not this......
>> pick [true false] none
== false After all.....
>> to-logic none
== false Either 'none is the logical equivalent of 'false or it isn't? As it currently stands as these examples show that this is the case except when it's not! and that hardly leads to consistency, clarity or ease of learnability and understanding. I think for clarity & consistency & simplicity this should be the case...... FALSE = NONE = 0 Reasoning...
>> to-logic none
== false
>> to-logic 0
== false
>> to-integer false
== 0
>> to-integer none
== 0 And if you give 'PICK the ability to utilise logic! or conditional values then saying
>> pick [true false] false
== false
>> pick [true false] 0
== false
>> pick [true false] none
== false IMHO Should be the "correct" behaviour however ally that to zero indexing for series! and preferably you would have this as the "correct" behaviour....
>> pick [false true] false
== false
>> pick [false true] 0
== false
>> pick [false true] none
== false
>> pick [false true] true
== true
>> pick [false true] 1
== true Simple, Consistent & easy to learn & remember! Certainly easier than False = 0 except when it equals 2 as we currently have. I think it was Volker who said "Plain English for Computers." Well as somebody who speaks english / scots as my natural language plain is hardly a term I would describe for the language. English as a language is an amalgation of Olde English / Germanic, Latin / French, Celtic / British, Norse, Pictish to name but a few of it's origins. I thought REBOL wanted to be "Simple, Powerful, Elegant" English whilst certainly Powerful and often extremely Elegant can in no ways be described as simple. The Cow -> Beef, Pig -> Pork, distinctions are only one example of multi-lingual variation in English. The former terms originate with the odle english / germanic names for the animals whereas the latter derive from french words for the flesh or meat of these animals and were introduced into english language in Norman times. Sure we all want context sensitivity and power of natural languages in REBOL but surely not also all the baggage & idiosyncracies of them as well? For me 'First is logically simple and compatable with Index position zero. I know this is all what-if anyway because what I have suggested is probably too deep a change for REBOL and would break backwards compatability of both source code AND existing documentation / books etc. so REBOL will most probably not be changed. However there is no harm in thinking / suggesting how simple, consistent and easier REBOL could be with no loss of power or expressability or elegance. REBOL 2.x came into being in 1998 so that is only 3 years backwards compatability. Surely we expect REBOL 3++ to be around a LOT longer than that, IMHO better to change now / then than live with inconsistency / the "wrong" way forever! And That is the Microsoft Way! Cheers, Mark Dickson In a message dated Tue, 3 Jul 2001 5:19:52 AM Eastern Daylight Time, Chris <[chris--starforge--demon--co--uk]> writes: << Romano Paolo Tenca wrote:
> The zero element of a series does not exist.
Unless you've programmed C for the best part of a decade, in which case all this talk of starting arrays and series at 1 takes a bit of getting used to.... ;) Chris -- New sig in the works Explorer2260 Designer and Coder