Re: CAP once more

From: [at]} <Bob>
Date: Fri, 17 Sep 2004 19:27:04 +0100

----boundary-LibPST-iamunique-2138431875_-_-
Content-type: text/plain

Hi H.,

> When you look at the output you will remark quite a lot of characters (of
> different gender, i. e. 'letter' and non 'letter') being mapped onto
> themselves whereas others of similar gender are not. So, if despite of
> speed it is possible to do this mapping why isn't it possible in the rest
> of the non sense cases resulting an intuitively understandable and at the
> same time foolproof function?

it is a consequence of the way CAP is defined and implemented in CP,
and of the way Latin-1 is coded.

Latin-1 is arranged in such a way that by ANDing the character with CHR(64)
the result, for letters, is either the capital version of the letter, or the
letter itself (e.g. if the input is 'A' then the output is 'A').

However, it does not work in this way for some non-letter characters; as you
have pointed out, CAP(CHR(247)) = CAP(÷) = ×

There is no sense in which ÷ can be said to have a capital letter, as
far as I know.

Other Oberons do not have a character set as part of the specification of
CAP, and none of them seems to specify the result of executing CAP on a
character like ÷, for which there is no meaningful capital equivalent.
Therefore, if you execute CAP with a non-letter character, all bets
are off. This is rather unfortunate. It would have been better to
define a result for the non-letter case. It should have returned
either the same character that was input, or it should have returned a
value such as 0X, indicating 'no corresponding capital'.

-- 
Regards,
 Bob
--------------------------------------------
To unsubscribe from this mailing list, send a message containing the word "unsubscribe" to:
   blackbox-request{([at]})nowhere.xyTo get a list of valid e-mail commands and instructions on their usage, send a message containing the word "help" to the above address.
Send any problem reports or questions related to this email list to the list owner at
   owner-blackbox{([at]})nowhere.xyCurrent posting policy:
a) To post you should use the same address by which you are subscribed to the mailing list. That way, the list server will recognize you as subscriber and forward your posting immediately, without creating any overhead.
b) If, for some reason, you cannot post from the address, by which you are subscribed, your message will be moderated to avoid spam. Please understand that moderation will often cause some delay, in particular over weekends or holydays.
----boundary-LibPST-iamunique-2138431875_-_-
Content-type: application/rtf
Content-transfer-encoding: base64
Content-Disposition: attachment; filename="rtf-body.rtf"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----boundary-LibPST-iamunique-2138431875_-_---
Received on Fri Sep 17 2004 - 20:27:04 UTC

This archive was generated by hypermail 2.3.0 : Thu Sep 26 2013 - 06:28:36 UTC