Mikael Tillenius wrote:
Thomas Lord wrote:
Yes. And, in practice, it is useful to implement them in different
ways and, at the same time, by which metrics we mean "efficient"
varies from situation to situation.
Yes. What I meant was that the specification in 5.92 is hard to
implement efficiently (e.g. string-ref is O(1)) if you want to store
the strings internally as utf8 or utf16. Some people want to do that.
Therefore (among other things) the current specification is
controversial.
Oh, well... my formal comment (submitted last night) would fix that.
The changes it advocates, alas, require more work than is present in the
proposal but hopefully it is enough to spark some interest in the direction.
-t
Firm up what *you* mean by "reasonable", give that thing a more
reasonable name than "reasonable", and refer to that.
Sorry but I'm vague on purpose here. But to give you some examples: It
is reasonable if things like string-ref, vector-ref is O(1) in time.
Its reasonable if a string with n characters use O(n) bytes. It is not
reasonable for string-ref and vector-ref to take O(n) time. It's not
reasonable for a string with n characters to use O(n^2) bytes of memory.
Another way to define what I mean by reasonable is to say that every
Scheme implementation I know about is reasonable.
Ok, were getting off topic here. To sum things up I think is is useful
to be able to assume certain things about time and memory consumption
in a programming language. Maybe it does not belong in the language
specification.
/Mikael
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