Re: parsability

From: "Hans-Peter Diettrich" <DrDiettrich1@netscape.net>
Sent: Monday, February 09, 2015 6:49 AM
> Robin Vowels schrieb:
>
>> A number of special characters have traditionally acquired multiple uses.
>> The asterisk, parentheses, apostrophe, colon, period, feature heavily
>> on account of the limited number of characters available in equipment
>> of the era (48-character set, 60 character set, etc.) and continue to do so
>> for historical reasons.
>
> IMO the real and persistent limit is the keyboard, with a limited number
> of keys.


Present keyboards for the PC have keys for 33 special characters
(in addition to upper and lower-case and digits).
That's twice as many in use in languages.


> Increasing the number of keys is not a solution, because then
> it may be more time consuming to find an special key, instead of reusing
> a character or typing more characters.


No need to increase the number of keys. Recall old typewriters?
Some had provision for three shifts (lower-case, upper-case, and special characters).
The same could be done with computer keyboards (well, it's sort of done with the normal, caps, and
CTRL keys).
A proper third shift key with corresponding glyphs inscribed on the keys
could extend the range of special characters. After all, there is provision for 256 characters
encoded in a byte, and we use only half of them.


>Why didn't APL succeed in the long run?


Because it was write once throw-away language.
Programs were largely unintelligible to all except the writer.


This email probably contains viruses and malware despite what avast! Antivirus protection says.
[It was perfectly possible to write readable APL programs, but almost
nobody did. -John]

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