I ran the tests several times, changing only the container and nothing more, but it is possible that the code was really incorrect somewhere, although I don't believe it. By the way, I usually set constructors and destructors to default, sometimes they (especially destructors) work at the wrong time, but I think this can also be explained by my inexperience in using them.

Сб, 28 дек. 2024 г. в 01:37, Jeremy Rifkin <rifkin.jer@gmail.com>:

> I meant that reset() simply resets the mSize counter, without performing any other logic.

If the items in the vector aren’t trivially destructible, this is a bug. Consider a vector of strings, you now have a memory leak.

> clear() from std::vector was noticeably faster than my `simple' clear() from FE2D::dynamic_array, but still fell short of reset()

I would be happy to look at implementation/benchmarks but my guess is this can be explained either by incorrect code or by incorrect benchmark setup. If the vector contents are trivially destructible then the extra logic from clear() is a no-op.

Cheers,

Jeremy

On Fri, Dec 27, 2024 at 15:30 Фаррах Фаттахов <farrakhfattahov@gmail.com> wrote:

I meant that reset() simply resets the mSize counter, without performing any other logic. However, I can't help but notice that during my tests, clear() from std::vector was noticeably faster than my `simple' clear() from FE2D::dynamic_array, but still fell short of reset()

Сб, 28 дек. 2024 г. в 01:23, Jeremy Rifkin <rifkin.jer@gmail.com>:

> Here reset() works like clear(), but much faster

Why? If you have in mind the destructor calls, those are important and can’t just be discarded. They will be optimized away by the compiler if the items are trivially destructed.

Cheers,

Jeremy

On Fri, Dec 27, 2024 at 14:57 Фаррах Фаттахов via Std-Proposals <std-proposals@lists.isocpp.org> wrote:

After working with SFML, I so hated std::vector (I was a bad programmer back then and didn't know about the reserve() function, which led to not understanding why std::vector is so slow, while a simple array performs much better). As a result, in my new project i created my own version of std::vector - FE2D::dynamic_array. And there, from the beginning i created one useful function - reset()

```C++

// Reset the Size of Dynamic Array to Zero, but it's don't Touches the Real Occupied Memory of Dynamic Array
void reset() { mSize = 0; }
```

Instead of clear() it's just setting mSize to zero. It's very useful in the situations like

```C++
void Render() { // It's called every frame
// Add a sprites to the FE2D::dynamic_array to draw it later
m_Renderer.AddSprite(m_Sprite_0);
m_Renderer.AddSprite(m_Sprite_1);
m_Renderer.AddSprite(m_Sprite_2);
...
// Draw the Sprites and reset the dynamic arrays to prepare it for the next frame
m_Renderer.RenderSprites();
}
```
Here reset() works like clear(), but much faster

In the std::vector or std::deque is no functions like reset() and i want to add it there, especially sometimes i get errors because my FE2D::dynamic_array is not so good like std::vector and i have to use it instead of mine, but there is no function i need. I think reset() will be nice thing for std::vector.

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