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/// Creates a [`Vec`] containing the arguments.↩
///↩
/// `vec!` allows `Vec`s to be defined with the same syntax as array expressions.↩
/// There are two forms of this macro:↩
///↩
/// - Create a [`Vec`] containing a given list of elements:↩
///↩
/// ```↩
/// use allocator_api2::vec;↩
/// let v = vec![1, 2, 3];↩
/// assert_eq!(v[0], 1);↩
/// assert_eq!(v[1], 2);↩
/// assert_eq!(v[2], 3);↩
/// ```↩
///↩
///↩
/// ```↩
/// use allocator_api2::{vec, alloc::Global};↩
/// let v = vec![in Global; 1, 2, 3];↩
/// assert_eq!(v[0], 1);↩
/// assert_eq!(v[1], 2);↩
/// assert_eq!(v[2], 3);↩
/// ```↩
///↩
/// - Create a [`Vec`] from a given element and size:↩
///↩
/// ```↩
/// use allocator_api2::vec;↩
/// let v = vec![1; 3];↩
/// assert_eq!(v, [1, 1, 1]);↩
/// ```↩
///↩
/// ```↩
/// use allocator_api2::{vec, alloc::Global};↩
/// let v = vec![in Global; 1; 3];↩
/// assert_eq!(v, [1, 1, 1]);↩
/// ```↩
///↩
/// Note that unlike array expressions this syntax supports all elements↩
/// which implement [`Clone`] and the number of elements doesn't have to be↩
/// a constant.↩
///↩
/// This will use `clone` to duplicate an expression, so one should be careful↩
/// using this with types having a nonstandard `Clone` implementation. For↩
/// example, `vec![Rc::new(1); 5]` will create a vector of five references↩
/// to the same boxed integer value, not five references pointing to independently↩
/// boxed integers.↩
///↩
/// Also, note that `vec![expr; 0]` is allowed, and produces an empty vector.↩
/// This will still evaluate `expr`, however, and immediately drop the resulting value, so↩
/// be mindful of side effects.↩
///↩
/// [`Vec`]: crate::vec::Vec↩
#[cfg(not(no_global_oom_handling))]↩
#[macro_export]↩
macro_rules! vec {↩
(in $alloc:expr $(;)?) => (↩
$crate::vec::Vec::new_in($alloc)↩
);↩
(in $alloc:expr; $elem:expr; $n:expr) => (↩
$crate::vec::from_elem_in($elem, $n, $alloc)↩
);↩
/*↩
(in $alloc:expr; $($x:expr),+ $(,)?) => (↩
$crate::boxed::Box::<[_]>::into_vec(↩
$crate::boxed::Box::slice(↩
$crate::boxed::Box::new_in([$($x),+], $alloc)↩
)↩
)↩
);↩
*/↩
() => (↩
$crate::vec::Vec::new()↩
);↩
($elem:expr; $n:expr) => (↩
$crate::vec::from_elem($elem, $n)↩
);↩
/*↩
($($x:expr),+ $(,)?) => (↩
$crate::boxed::Box::<[_]>::into_vec(↩
$crate::boxed::Box::slice(↩
$crate::boxed::Box::new([$($x),+])↩
)↩
)↩
);↩
*/↩
}↩