use beef::lean::Cow;
use std::{ops::Index, slice::SliceIndex};
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct Query<'a, T: Clone>(Cow<'a, [T]>);
impl<'a, T: Clone> Query<'a, T> {
pub fn new<C>(beef: C) -> Self
where
C: Into<Cow<'a, [T]>>,
{
Query(beef.into())
}
#[must_use]
pub fn is_empty(&self) -> bool {
self.0.is_empty()
}
#[must_use]
pub fn len(&self) -> usize {
self.0.len()
}
#[must_use]
pub fn into_inner(self) -> Cow<'a, [T]> {
self.0
}
#[must_use]
pub fn into_owned(self) -> Vec<T> {
self.0.into_owned()
}
}
impl<I: SliceIndex<[T]>, T: Clone> Index<I> for Query<'_, T> {
type Output = I::Output;
fn index(&self, index: I) -> &Self::Output {
self.0.index(index)
}
}
pub trait ToQuery<T: Clone> {
fn to_query(&self) -> Query<'_, T>;
}
impl<T: Clone> ToQuery<T> for Query<'_, T> {
fn to_query(&self) -> Query<'_, T> {
Query::new(&self[..])
}
}
impl<T: Clone> ToQuery<T> for [T] {
fn to_query(&self) -> Query<'_, T> {
Query::new(self)
}
}
impl<'a, T: Clone> ToQuery<T> for &'a [T] {
fn to_query(&self) -> Query<'a, T> {
Query::new(*self)
}
}
impl<T: Clone> ToQuery<T> for Vec<T> {
fn to_query(&self) -> Query<'_, T> {
Query::new(self.as_slice())
}
}
impl<T: Clone, const L: usize> ToQuery<T> for [T; L] {
fn to_query(&self) -> Query<'_, T> {
Query::new(self.as_slice())
}
}
#[macro_export]
macro_rules! query {
($($x:expr),*) => (
$crate::ToQuery::to_query(&[$($x),*])
);
}