Don wrote:
Ary Borenszweig wrote:
Don wrote:
Ary Borenszweig wrote:
Don wrote:
Lars T. Kyllingstad wrote:
Don wrote:
bearophile wrote:
So far I've just given a light reading of the code. Notes:
- pow(x, 2) and sqrt(y) can be written as x ^^ 2 and y ^^ 0.5
(but you have to import std.math anyway, because of a bug).
That's not a bug. It's intentional. x ^^ y will probably always
require import std.math, if y is a floating point number.
Really? Why is that? I find that kind of disappointing, I always
believed it to be a temporary solution.
I think the inconsistency with the other operators will make this
a major WTF for people new to the language. Why should a^^b
require an explicit import while a*b doesn't?
Because pow() for floating point, when implemented properly, is a
HUGE function, that ends up dragging almost all of std.math into
the executable. And I think it's deceptive to do that silently.
To make it completely built-in, basically all of std.math would
need to be moved into druntime. Feel free to try to change my mind,
of course.
Is there a better way to do pow() for floating point numbers without
importing std.math?
I see this:
1. You want to do x ^^ fp.
2. The compiler complains saying "if you want to do that, import
std.math. I'm telling you this just to let you know you'll be
importing the whole module".
Alternative 1 for user:
User says "Ok, I import std.math"
Alternative 2 for user:
User says "No way I'm importing std.math just to make a pow. But...
I still *need* to make that pow... what is your advice, mr. compiler?"
That's a good point, it should be possible to use a static import as
well. I do think it's pretty odd to be doing floating point without
importing std.math, though. I mean, abs() is absolutely fundamental.
But if you do a static import the whole module gets linked in, right?
My point is, if you are going to pow, you will need std.math, so it'll
always be a burden to import it by hand when using it. ^^
But you're assuming that you're using ^^ without using anything else
from std.math. I think that's a very obscure case.
For example, any code which is ported from C or C++, or D1, that uses
pow, will already be importing std.math. Cases where you see that you
could use ^^ that isn't already using pow() (eg, where you see z = x*x +
y*y), you will need to add an import.
- Oh, hi Foo, I want to show you this great language D. You can doo blah
and bleh.
- Cool, I will code something little to see how it is.
...
Hey, WTF, I use the pow operand and it tells me I need to add an
import? WTF??
You know, people program from scratch, they don't spend their life
porting C and C++ code... ^^
