binary selectors ambiguity and space
helbig at Lehre.BA-Stuttgart.DE
Sat May 13 20:46:45 UTC 2006
>Well, the *idea* was that you should not need spaces, and St-76, borrowing from
>APL, had a different character for the semantically different high-minus sign
What's so bad about needing spaces? After all, the space key is one of the
easiest to hit :-). And spaces are already required as separators between
keywords and argument names, aren't they?. It seems quite natural to require
spaces as separators between a binary selector and a "special character" like
Then you could get rid of the special treatment of the minus character. That is,
the minus character would be allowed as a second character of a binary selector.
This change would simplify the grammar and slightly enlarge the expressivenes of
the language -- at the cost of needing a separator between the one character
binary selector #- followed by a minus as part of a number literal.
Here is the change of the grammar expressed in EBNF:
+ | - | / | \ | * | ~ | < | > | = | @ | % | | | & | ? | ! | ,
binary_selector ::= special_character [special_character]
See also at
for the EBNF meta characters and some other modifications I've proposed for the
Weniger, aber besser.
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