On 10.08.2010 02:46, Jonathan M Davis wrote:
On Monday, August 09, 2010 17:24:47 simendsjo wrote:
\r and \n is used many times throughout std.string (and probably other
modules like file).
I assume defining constants were considered:
const CR = '\r';
const LF = '\n';
So why isn't constants used instead?
Well, what would that really save or help? They're totally unambiguous and
easily typed with the keyboard. Not to mention, if you were going to do that,
you'd probably define them like so
enum CR = "\r";
enum LF = "\n";
Using enum for manifest constants is the more typical way to do it in D (it also
forces compile-time evaluation of their value), and we want to avoid using
individual chars or wchars, so pretty much all string-related functions take
strings even if you'd think that they'd take a character of some kind (though if
they were to take a character type, it would have to be dchar).
In any case, the values for these constants never change regardless of the
machine - unlike something like path.sep which indicates the path separator for
the machine and changes depending on which machine you compile on. For it to be
worth making "\r" and "\n" constants, you have to gain something from it, and I
don't think that there's much to be gained. Not to mention, you can always make
more constants, and you have to stop somewhere, so you're always going to find
something that _could_ be a constant and isn't.
- Jonathan M Davis
I agree. I really don't thing it makes a difference or not.. '\r' is
always that symbol no matter if it's a iPhone, embedded device or
supercomputer. It's more that it's more error prone to write it than CR
(ooops! compiler error!). If I wrote '\e' in a large switch and haven't
tested all code paths.. Yes, shame on me, but I really meant \r! A
constant gives me an at once. D is all about removing common, stupid
programmer errors like I do, right? :)
It's just nitpicking and not a big deal at all. I can only remember once
I've been bitten by one of these (not in D), but I quickly found the source.
