[RFC]: replace `copyView` in `ndarray/array/lib/copy_view.js` with `ndarray/copy`

[Aniket-SS]

Description

In ndarray/array/lib/copy_view.js, the copyView function manually creates an output buffer, constructs a plain ndarray-like
object, and uses ndarray/base/assign to copy data.

The function contains the following TODO comment:

function copyView( arr, dtype ) { // TODO: consider replacing with `@stdlib/ndarray[/base]/copy` once created

Now that ndarray/copy exists, the manual logic can be replaced by importing ndarray/copy, removing the following unnecessary imports:

• @stdlib/ndarray/base/assert/is-equal-data-type
• @stdlib/buffer/alloc-unsafe
• @stdlib/ndarray/base/buffer-ctors
• @stdlib/ndarray/order
• @stdlib/ndarray/base/numel
• @stdlib/ndarray/base/shape2strides
• @stdlib/ndarray/base/assign
• @stdlib/array/base/zeros

[stdlib-bot]

👋 Hi there! 👋

And thank you for opening your first issue! We will get back to you shortly. 🏃 💨

If you have any further questions while waiting for a response, please join our Zulip community to chat with project maintainers and other community members.

[Aniket-SS]

While working on the TODO, I found that ndarray/copy cannot fully replace copyView because it uses isMostlySafeCast to validate dtype casting, which rejects certain casts that copyView currently supports (e.g., generic to float64).

if ( !isMostlySafeCast( dt, options.dtype ) ) {
    throw new TypeError( ... )
}

CC: @kgryte

[kgryte]

And...what did you find with ndarray/base/copy? Would that work? Why or why not?

[kgryte]

In short, note that the comment says "consider replacing with". There may be reasons why we haven't yet. You should think through those reasons.

[Aniket-SS]

And...what did you find with ndarray/base/copy? Would that work? Why or why not?

ndarray/base/copy copies an input ndarray to a new ndarray having the same shape and data type. Hence it would not work as it does not accepts a target dtype for casting in its arguments.