impl_owned_array.rs

use std::prelude::v1::*;
use crate::imp_prelude::*;

/// Methods specific to `Array0`.
///
/// ***See also all methods for [`ArrayBase`]***
///
/// [`ArrayBase`]: struct.ArrayBase.html
impl<A> Array<A, Ix0> {
    /// Returns the single element in the array without cloning it.
    ///
    /// ```
    /// use ndarray::{arr0, Array0};
    ///
    /// // `Foo` doesn't implement `Clone`.
    /// #[derive(Debug, Eq, PartialEq)]
    /// struct Foo;
    ///
    /// let array: Array0<Foo> = arr0(Foo);
    /// let scalar: Foo = array.into_scalar();
    /// assert_eq!(scalar, Foo);
    /// ```
    pub fn into_scalar(mut self) -> A {
        let size = ::std::mem::size_of::<A>();
        if size == 0 {
            // Any index in the `Vec` is fine since all elements are identical.
            self.data.0.remove(0)
        } else {
            // Find the index in the `Vec` corresponding to `self.ptr`.
            // (This is necessary because the element in the array might not be
            // the first element in the `Vec`, such as if the array was created
            // by `array![1, 2, 3, 4].slice_move(s![2])`.)
            let first = self.ptr.as_ptr() as usize;
            let base = self.data.0.as_ptr() as usize;
            let index = (first - base) / size;
            debug_assert_eq!((first - base) % size, 0);
            // Remove the element at the index and return it.
            self.data.0.remove(index)
        }
    }
}

/// Methods specific to `Array`.
///
/// ***See also all methods for [`ArrayBase`]***
///
/// [`ArrayBase`]: struct.ArrayBase.html
impl<A, D> Array<A, D>
where
    D: Dimension,
{
    /// Return a vector of the elements in the array, in the way they are
    /// stored internally.
    ///
    /// If the array is in standard memory layout, the logical element order
    /// of the array (`.iter()` order) and of the returned vector will be the same.
    pub fn into_raw_vec(self) -> Vec<A> {
        self.data.0
    }
}