Can somebody give me an example of using an "open interval for the upper limit of a range"?

[Jonathan M Davis]

On Wednesday, March 12, 2025 12:07:04 PM MDT Manfred Nowak via Digitalmars-d-learn wrote:
> On Tuesday, 11 March 2025 at 16:56:28 UTC, WhatMeWorry wrote:
> [...]
> > To include the upper bound value, use a square bracket "]" at
> > the end of the range."
>
> [...]
> > foreach( i, e; a[0..3] )
> >     write(i, ":", e);  // 0:11  1:22  2:3
>
> That example negates the claim of that Citation already!
>
> Although a square bracket follows the range "0..3", neither the
> index '3´ nor the value of 'a[3]´ are remarked---and are not
> written indeed.

In mathematics and computer science in general, it's very common in the
notation of ranges / intervals of numbers to use ] at the end of the range
of values when the last number is inclusive, and ) when it's exclusive. So,
I could definitely see some of the documentation using such notation when
explaining things (though I don't recall seeing that anywhere off the top of
my head). However, it definitely isn't something that's a syntactic part of
how D handles anything. As Ali mention, it looks like std.random does use [
and ) in strings used as template arguments to specify the behavior of some
functions, but that's probably the closest that we actually have to it being
part of the language itself.

So, I don't know what part of the documentation that WhatMeWorry read which
gave him the impression that the language itself uses ] or ) in any of its
syntax to indicate how open an interval is, but it implies that either
something we have was not written clearly enough (which is very possible) or
that WhatMeWorry misinterpreted it in an unusual way.

- Jonathan M Davis