On Monday, 7 October 2019 at 19:16:31 UTC, IGotD- wrote:
On Monday, 7 October 2019 at 17:36:09 UTC, Ferhat Kurtulmuş
wrote:
I'm not talking about memory deletion. I'm talking about
push, pop, enqueue, and dequeue behavior. I'd assume in a
garbage collected language letting the reference float off
should be picked up by the GC.
I'm sorry. Writing on my mobile phone. Maybe this is what you
are looking for
https://dlang.org/phobos/std_container_dlist.html
I think what he is looking for are the general pop_front,
push_front, pop_back and push_back that you would find in
virtually any C++ STL container algorithms like list, vector or
map.
I think this is a good question as I don't really see any good
example in the documentation of the dynamic arrays about this.
This is very common use case for arrays. Is there any D
equivalent?
With the performance that you'd expect, I believe:
#! /usr/bin/env rdmd
import std.stdio;
import std.algorithm : moveAll;
void push_front(T)(ref T[] xs, T x) {
++xs.length;
moveAll(xs[0 .. $-1], xs[1..$]);
x[0] = x;
}
T pop_front(T)(ref T[] xs) {
T x = xs[0];
moveAll(xs[1 .. $], xs[0 .. $-1]);
--xs.length;
return x;
}
void push_back(T)(ref T[] xs, T x) {
xs ~= x;
}
T pop_back(T)(ref T[] xs) {
T x = xs[$ - 1];
--xs.length;
return x;
}
void main() {
int[] xs;
foreach (i; 0 .. 10)
xs.push_back(i);
writeln(xs.pop_back()); // output: 9
writeln(xs.pop_front()); // output: 0
writeln(xs.pop_front()); // output: 1
writeln(xs); // output: [2, 3, 4, 5, 6, 7, 8]
}
