Jérôme M. Berger wrote:
Andrei Alexandrescu wrote:
Jérôme M. Berger wrote:
Andrei Alexandrescu wrote:
Jérôme M. Berger wrote:
Andrei Alexandrescu wrote:
Derek Parnell wrote:
It seems that D would benefit from having a standard syntax
format for
expressing various range sets;
a. Include begin Include end, i.e. []
b. Include begin Exclude end, i.e. [)
c. Exclude begin Include end, i.e. (]
d. Exclude begin Exclude end, i.e. ()
I'm afraid this would majorly mess with pairing of parens.
I think Derek's point was to have *some* syntax to mean this,
not necessarily the one he showed (which he showed because I
believe that's the "standard" mathematical way to express it for
English speakers). For example, we could say that [] is always
inclusive and have another character which makes it exclusive like:
a. Include begin Include end, i.e. [ a .. b ]
b. Include begin Exclude end, i.e. [ a .. b ^]
c. Exclude begin Include end, i.e. [^ a .. b ]
d. Exclude begin Exclude end, i.e. [^ a .. b ^]
I think Walter's message really rendered the whole discussion moot.
Post of the year:
=========================
I like:
a .. b+1
to mean inclusive range.
=========================
Consider "+1]" a special symbol that means the range is to be closed
to the right :o).
Ah, but:
- This is inconsistent between the left and right limit;
- This only works for integers, not for floating point numbers.
How does it not work for floating point numbers?
Is that a trick question? Depending on the actual value of b, you
might have b+1 == b (if b is large enough). Conversely, range a .. b+1
may contain a lot of extra numbers I may not want to include (like
b+0.5)...
It wasn't a trick question, or it was of sorts. If you iterate with e.g.
foreach through a floating-point range that has b == b + 1, you're bound
to get in a lot of trouble because the running variable will be
incremented.
Andrei
