remove element from dyn array by element, (not by index)

[bearophile]

This may help clear your mind some:

import std.stdio: writefln;
import std.string: format;

void removeBang(T)(ref T[] arr, T el) {
    foreach(i, x; arr)
        if (x == el) {
            arr = arr[0 .. i] ~ arr[i+1 .. $];
            break;
        }
}

class C(bool withEqual) {
    int x;
    this(int x) {
        this.x = x;
    }
    string toString() {
        return format("C(%d)", x);
    }
    static if (withEqual) {
        bool opEquals(C other) {
            return this.x == other.x;
        }
    }
}

void main() {
    int[] a = [1, 2, 3, 4, 1];
    writefln(a);
    a.removeBang(4);
    writefln(a);
    writefln;

    alias C!(true) C1;
    auto b = new C1(2);
    C1[] oa = [new C1(1), b, new C1(3)];
    removeBang(oa, b);
    writefln(oa);
    removeBang(oa, new C1(1));
    writefln(oa);
    writefln;

    alias C!(false) C2;
    auto b2 = new C2(2);
    C2[] oa2 = [new C2(1), b2, new C2(3)];
    removeBang(oa2, b2);
    writefln(oa2);
    removeBang(oa2, new C2(1));
    writefln(oa2);
}


Output:

[1,2,3,4,1]
[1,2,3,1]

[C(1),C(3)]
[C(3)]

[C(1),C(3)]
[C(1),C(3)]

Bye,
bearophile