On Wednesday, 29 March 2023 at 19:49:47 UTC, Ali Çehreli wrote:
> On 3/29/23 12:21, ag0aep6g wrote:
> As far as I understand, you're saying that we cannot overload
on ref.
But we can. Salih's code demonstrates just that.
void f(ref int x) {}
void f(int x) {}
void main() { int x; f(x); f(42); } /* no errors */
I thought Salih was proposing two more overloads to the existing put(). When I copy the existing put(), which takes 'ref R', not R[], then the code does not compile:
Wait a minute, isn't copy actually a put as well? Forget about ref for a moment, please. Actually, logically, the parameters have been swapped between the two functions. Well, if we only had copy and we used put like copy, what is the need for put? Examples are below: :)
//version = simple;/*
version = standart;//*/
version(simple) {
auto put(R)(R[] range, R[] source)
=> copyImpl(source, range);
auto copy(R)(R[] source, R[] range)
=> copyImpl(source, range);
auto copyImpl(R)(R[] source, R[] range)
{
assert(source.length <= range.length);
foreach(element; source)
{
range[0] = element; // range.front()
range = range[1..$]; // range.popFront()
}
return range;
}
void swap (ref int x, ref int y)
{
x = x ^ y;
y = y ^ x;
x = x ^ y;
}
}
version(standart)
import std.algorithm.mutation,
std.range : put;
void main()
{
// copy() example:
enum len = 10;
auto buf = new int[len]; // buffer
auto dig = [7, 1, 2, 3]; // digits
auto diff = len - dig.length;
auto rem = copy(dig, buf);
assert(buf[0..$ - diff] == [7, 1, 2, 3]);
swap(buf[0], rem[0]);
assert(rem == [7, 0, 0, 0, 0, 0]);
// put() example 1:
put(rem, [4, 5, 6, 7, 8, 9]);
assert(buf == [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
// put() example 2:
enum data = [1, 0, 0, 4];
auto arr = data;
auto slice = arr[1..$-1];
version(standart)
put(slice, [2]);
version(simple)
slice = put(slice, [2]);
assert(arr == [1, 2, 0, 4]);
version(standart)
put(slice, [3]);
version(simple)
slice = put(slice, [3]);
assert(arr == [1, 2, 3, 4]);
version(standart) {
auto slc = arr[1..$-1];
put(slc, [0, 0]);
}
version(simple)
arr[1..$-1].put([0, 0]);
assert(arr == data);
}
All you have to do is remove the // mark in the first line. The code compiles for me, what about you?
SDB@79
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