On 11/11/10 9:52 AM, Daniel Gibson wrote:
Andrei Alexandrescu schrieb:
On 11/11/10 9:25 AM, Daniel Gibson wrote:
Jonathan M Davis schrieb:
On Wednesday, November 10, 2010 14:52:10 Jesse Phillips wrote:
Walter Bright Wrote:
dsimcha wrote:
Libraries need to make the
simple use cases sufficiently simple that people aren't tempted to
roll
their own.
Hear hear. For example, one of the goals with D strings was to make
them
so good that people wouldn't invent their own string classes.
And yet we still get those that want a class, or even limit the
capability
of arrays so that a class is more appealing. (Had a friend that hated
the
idea that D went back to array of characters, then he saw that arrays
could actually do stuff)
Well, of course his first reaction was negative. Arrays suck in other
languages in comparison to D. Having strings be arrays in C is
horrible. I'd be annoyed to have strings be arrays if you were using
Java arrays, and they're a definite improvement over C - if nothing
else because they know their length. Strings as arrays work in D
precisely because D arrays are so awesome. I've never used another
language which had arrays which were even close to as awesome as the
ones in D.
- Jonathan M Davis
The only possible source of confusion may be that slicing is only safe
with dchar[]. (But still may work with char[] as long as you're only
using ASCII characters, so the error may not be obvious)
Of course I don't want to propose to change that because it makes
perfect sense the way it is, because in many situations you want to
know, how long the string physically is (how many bytes), so any hack to
splice by logical characters instead of physical characters would result
in a terrible mess.
But this is something a string-class with .substring(beg, end),
.logLength, .physLength and stuff like that could fix, because these
differences were more obvious.
But then again, having the following functions in std.string may
suffice:
size_t logLength(string s) // logical length in code points
That would be walkLength.
Ok. I really should get familiar with std.algorithm and D2 in general :-)
string substring(string s, size_t beg, size_t end) // "logical slice" -
from code point number beg to code point number end
That's not implemented and I don't think it would be useful. Usually
when I want a substring, the calculations up to that point indicate
the code _unit_ I'm at.
On the other hand those wouldn't play nice with the existing functions
like indexOf etc :/
Hm, I just noticed a problem. std.algorithm.indexOf returns logical
position because it uses the forward range interface, and
std.string.indexOf returns the physical position :o(.
I'm glad to have accidentally revealed that inconsistency ;)
Probably something should be done about this, maybe by renaming one of
the functions or something like that?
Yah, this is worth a bug report. Thanks.
http://d.puremagic.com/issues/show_bug.cgi?id=5201
Andrei
