Added FuseIteratorImpl, FustDoubleEndedIteratorImpl and FuseExactSizeIteratorImpl to avoid exposing default functions outside of the current crate.
This commit is contained in:
Rakshith Ravi
parent
af89eb5e5b
commit
0a54a9403d
1 changed files with 275 additions and 104 deletions
|
|
@ -51,6 +51,182 @@ where
|
|||
{
|
||||
type Item = <I as Iterator>::Item;
|
||||
|
||||
#[inline]
|
||||
fn next(&mut self) -> Option<Self::Item> {
|
||||
FuseIteratorImpl::next(self)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn nth(&mut self, n: usize) -> Option<I::Item> {
|
||||
FuseIteratorImpl::nth(self, n)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn last(self) -> Option<Self::Item> {
|
||||
FuseIteratorImpl::last(self)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn count(self) -> usize {
|
||||
FuseIteratorImpl::count(self)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn size_hint(&self) -> (usize, Option<usize>) {
|
||||
FuseIteratorImpl::size_hint(self)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn try_fold<Acc, Fold, R>(&mut self, acc: Acc, fold: Fold) -> R
|
||||
where
|
||||
Self: Sized,
|
||||
Fold: FnMut(Acc, Self::Item) -> R,
|
||||
R: Try<Ok = Acc>,
|
||||
{
|
||||
FuseIteratorImpl::try_fold(self, acc, fold)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn fold<Acc, Fold>(self, acc: Acc, fold: Fold) -> Acc
|
||||
where
|
||||
Fold: FnMut(Acc, Self::Item) -> Acc,
|
||||
{
|
||||
FuseIteratorImpl::fold(self, acc, fold)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
|
||||
where
|
||||
P: FnMut(&Self::Item) -> bool,
|
||||
{
|
||||
FuseIteratorImpl::find(self, predicate)
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<I> DoubleEndedIterator for Fuse<I>
|
||||
where
|
||||
I: DoubleEndedIterator,
|
||||
{
|
||||
#[inline]
|
||||
fn next_back(&mut self) -> Option<<I as Iterator>::Item> {
|
||||
FuseDoubleEndedIteratorImpl::next_back(self)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn nth_back(&mut self, n: usize) -> Option<<I as Iterator>::Item> {
|
||||
FuseDoubleEndedIteratorImpl::nth_back(self, n)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn try_rfold<Acc, Fold, R>(&mut self, acc: Acc, fold: Fold) -> R
|
||||
where
|
||||
Self: Sized,
|
||||
Fold: FnMut(Acc, Self::Item) -> R,
|
||||
R: Try<Ok = Acc>,
|
||||
{
|
||||
FuseDoubleEndedIteratorImpl::try_rfold(self, acc, fold)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn rfold<Acc, Fold>(self, acc: Acc, fold: Fold) -> Acc
|
||||
where
|
||||
Fold: FnMut(Acc, Self::Item) -> Acc,
|
||||
{
|
||||
FuseDoubleEndedIteratorImpl::rfold(self, acc, fold)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item>
|
||||
where
|
||||
P: FnMut(&Self::Item) -> bool,
|
||||
{
|
||||
FuseDoubleEndedIteratorImpl::rfind(self, predicate)
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<I> ExactSizeIterator for Fuse<I>
|
||||
where
|
||||
I: ExactSizeIterator,
|
||||
{
|
||||
fn len(&self) -> usize {
|
||||
FuseExactSizeIteratorImpl::len(self)
|
||||
}
|
||||
|
||||
fn is_empty(&self) -> bool {
|
||||
FuseExactSizeIteratorImpl::is_empty(self)
|
||||
}
|
||||
}
|
||||
|
||||
// NOTE: for `I: FusedIterator`, we assume that the iterator is always `Some`.
|
||||
// Implementing this as a directly-expanded macro helps codegen performance.
|
||||
macro_rules! unchecked {
|
||||
($self:ident) => {
|
||||
match $self {
|
||||
Fuse { iter: Some(iter) } => iter,
|
||||
// SAFETY: the specialized iterator never sets `None`
|
||||
Fuse { iter: None } => unsafe { intrinsics::unreachable() },
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
#[stable(feature = "fused", since = "1.26.0")]
|
||||
impl<I> Iterator for Fuse<I> where I: FusedIterator {}
|
||||
|
||||
#[stable(feature = "fused", since = "1.26.0")]
|
||||
impl<I> DoubleEndedIterator for Fuse<I> where I: DoubleEndedIterator + FusedIterator {}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<I> ExactSizeIterator for Fuse<I> where I: ExactSizeIterator + FusedIterator {}
|
||||
|
||||
unsafe impl<I> TrustedRandomAccess for Fuse<I>
|
||||
where
|
||||
I: TrustedRandomAccess,
|
||||
{
|
||||
unsafe fn get_unchecked(&mut self, i: usize) -> I::Item {
|
||||
match self.iter {
|
||||
Some(ref mut iter) => iter.get_unchecked(i),
|
||||
// SAFETY: the caller asserts there is an item at `i`, so we're not exhausted.
|
||||
None => intrinsics::unreachable(),
|
||||
}
|
||||
}
|
||||
|
||||
fn may_have_side_effect() -> bool {
|
||||
I::may_have_side_effect()
|
||||
}
|
||||
}
|
||||
|
||||
// Fuse specialization trait
|
||||
#[doc(hidden)]
|
||||
trait FuseIteratorImpl<I> {
|
||||
type Item;
|
||||
fn next(&mut self) -> Option<Self::Item>;
|
||||
fn nth(&mut self, n: usize) -> Option<Self::Item>;
|
||||
fn last(self) -> Option<Self::Item>;
|
||||
fn count(self) -> usize;
|
||||
fn size_hint(&self) -> (usize, Option<usize>);
|
||||
fn try_fold<Acc, Fold, R>(&mut self, acc: Acc, fold: Fold) -> R
|
||||
where
|
||||
Self: Sized,
|
||||
Fold: FnMut(Acc, Self::Item) -> R,
|
||||
R: Try<Ok = Acc>;
|
||||
fn fold<Acc, Fold>(self, acc: Acc, fold: Fold) -> Acc
|
||||
where
|
||||
Fold: FnMut(Acc, Self::Item) -> Acc;
|
||||
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
|
||||
where
|
||||
P: FnMut(&Self::Item) -> bool;
|
||||
}
|
||||
|
||||
// General Fuse impl
|
||||
#[doc(hidden)]
|
||||
impl<I> FuseIteratorImpl<I> for Fuse<I>
|
||||
where
|
||||
I: Iterator,
|
||||
{
|
||||
type Item = <I as Iterator>::Item;
|
||||
|
||||
#[inline]
|
||||
default fn next(&mut self) -> Option<<I as Iterator>::Item> {
|
||||
fuse!(self.iter.next())
|
||||
|
|
@ -119,89 +295,8 @@ where
|
|||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<I> DoubleEndedIterator for Fuse<I>
|
||||
where
|
||||
I: DoubleEndedIterator,
|
||||
{
|
||||
#[inline]
|
||||
default fn next_back(&mut self) -> Option<<I as Iterator>::Item> {
|
||||
fuse!(self.iter.next_back())
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn nth_back(&mut self, n: usize) -> Option<<I as Iterator>::Item> {
|
||||
fuse!(self.iter.nth_back(n))
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn try_rfold<Acc, Fold, R>(&mut self, mut acc: Acc, fold: Fold) -> R
|
||||
where
|
||||
Self: Sized,
|
||||
Fold: FnMut(Acc, Self::Item) -> R,
|
||||
R: Try<Ok = Acc>,
|
||||
{
|
||||
if let Some(ref mut iter) = self.iter {
|
||||
acc = iter.try_rfold(acc, fold)?;
|
||||
self.iter = None;
|
||||
}
|
||||
Try::from_ok(acc)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn rfold<Acc, Fold>(self, mut acc: Acc, fold: Fold) -> Acc
|
||||
where
|
||||
Fold: FnMut(Acc, Self::Item) -> Acc,
|
||||
{
|
||||
if let Some(iter) = self.iter {
|
||||
acc = iter.rfold(acc, fold);
|
||||
}
|
||||
acc
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item>
|
||||
where
|
||||
P: FnMut(&Self::Item) -> bool,
|
||||
{
|
||||
fuse!(self.iter.rfind(predicate))
|
||||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<I> ExactSizeIterator for Fuse<I>
|
||||
where
|
||||
I: ExactSizeIterator,
|
||||
{
|
||||
default fn len(&self) -> usize {
|
||||
match self.iter {
|
||||
Some(ref iter) => iter.len(),
|
||||
None => 0,
|
||||
}
|
||||
}
|
||||
|
||||
default fn is_empty(&self) -> bool {
|
||||
match self.iter {
|
||||
Some(ref iter) => iter.is_empty(),
|
||||
None => true,
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// NOTE: for `I: FusedIterator`, we assume that the iterator is always `Some`.
|
||||
// Implementing this as a directly-expanded macro helps codegen performance.
|
||||
macro_rules! unchecked {
|
||||
($self:ident) => {
|
||||
match $self {
|
||||
Fuse { iter: Some(iter) } => iter,
|
||||
// SAFETY: the specialized iterator never sets `None`
|
||||
Fuse { iter: None } => unsafe { intrinsics::unreachable() },
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
#[stable(feature = "fused", since = "1.26.0")]
|
||||
impl<I> Iterator for Fuse<I>
|
||||
#[doc(hidden)]
|
||||
impl<I> FuseIteratorImpl<I> for Fuse<I>
|
||||
where
|
||||
I: FusedIterator,
|
||||
{
|
||||
|
|
@ -257,8 +352,77 @@ where
|
|||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "fused", since = "1.26.0")]
|
||||
impl<I> DoubleEndedIterator for Fuse<I>
|
||||
#[doc(hidden)]
|
||||
trait FuseDoubleEndedIteratorImpl<I> {
|
||||
type Item;
|
||||
fn next_back(&mut self) -> Option<Self::Item>;
|
||||
fn nth_back(&mut self, n: usize) -> Option<Self::Item>;
|
||||
fn try_rfold<Acc, Fold, R>(&mut self, acc: Acc, fold: Fold) -> R
|
||||
where
|
||||
Self: Sized,
|
||||
Fold: FnMut(Acc, Self::Item) -> R,
|
||||
R: Try<Ok = Acc>;
|
||||
fn rfold<Acc, Fold>(self, acc: Acc, fold: Fold) -> Acc
|
||||
where
|
||||
Fold: FnMut(Acc, Self::Item) -> Acc;
|
||||
fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item>
|
||||
where
|
||||
P: FnMut(&Self::Item) -> bool;
|
||||
}
|
||||
|
||||
#[doc(hidden)]
|
||||
impl<I> FuseDoubleEndedIteratorImpl<I> for Fuse<I>
|
||||
where
|
||||
I: DoubleEndedIterator,
|
||||
{
|
||||
type Item = <I as Iterator>::Item;
|
||||
|
||||
#[inline]
|
||||
default fn next_back(&mut self) -> Option<<I as Iterator>::Item> {
|
||||
fuse!(self.iter.next_back())
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn nth_back(&mut self, n: usize) -> Option<<I as Iterator>::Item> {
|
||||
fuse!(self.iter.nth_back(n))
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn try_rfold<Acc, Fold, R>(&mut self, mut acc: Acc, fold: Fold) -> R
|
||||
where
|
||||
Self: Sized,
|
||||
Fold: FnMut(Acc, Self::Item) -> R,
|
||||
R: Try<Ok = Acc>,
|
||||
{
|
||||
if let Some(ref mut iter) = self.iter {
|
||||
acc = iter.try_rfold(acc, fold)?;
|
||||
self.iter = None;
|
||||
}
|
||||
Try::from_ok(acc)
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn rfold<Acc, Fold>(self, mut acc: Acc, fold: Fold) -> Acc
|
||||
where
|
||||
Fold: FnMut(Acc, Self::Item) -> Acc,
|
||||
{
|
||||
if let Some(iter) = self.iter {
|
||||
acc = iter.rfold(acc, fold);
|
||||
}
|
||||
acc
|
||||
}
|
||||
|
||||
#[inline]
|
||||
default fn rfind<P>(&mut self, predicate: P) -> Option<Self::Item>
|
||||
where
|
||||
P: FnMut(&Self::Item) -> bool,
|
||||
{
|
||||
fuse!(self.iter.rfind(predicate))
|
||||
}
|
||||
}
|
||||
|
||||
#[doc(hidden)]
|
||||
impl<I> FuseDoubleEndedIteratorImpl<I> for Fuse<I>
|
||||
where
|
||||
I: DoubleEndedIterator + FusedIterator,
|
||||
{
|
||||
|
|
@ -299,8 +463,32 @@ where
|
|||
}
|
||||
}
|
||||
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
impl<I> ExactSizeIterator for Fuse<I>
|
||||
#[doc(hidden)]
|
||||
trait FuseExactSizeIteratorImpl<I> {
|
||||
fn len(&self) -> usize;
|
||||
fn is_empty(&self) -> bool;
|
||||
}
|
||||
|
||||
impl<I> FuseExactSizeIteratorImpl<I> for Fuse<I>
|
||||
where
|
||||
I: ExactSizeIterator,
|
||||
{
|
||||
default fn len(&self) -> usize {
|
||||
match self.iter {
|
||||
Some(ref iter) => iter.len(),
|
||||
None => 0,
|
||||
}
|
||||
}
|
||||
|
||||
default fn is_empty(&self) -> bool {
|
||||
match self.iter {
|
||||
Some(ref iter) => iter.is_empty(),
|
||||
None => true,
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<I> FuseExactSizeIteratorImpl<I> for Fuse<I>
|
||||
where
|
||||
I: ExactSizeIterator + FusedIterator,
|
||||
{
|
||||
|
|
@ -312,20 +500,3 @@ where
|
|||
unchecked!(self).is_empty()
|
||||
}
|
||||
}
|
||||
|
||||
unsafe impl<I> TrustedRandomAccess for Fuse<I>
|
||||
where
|
||||
I: TrustedRandomAccess,
|
||||
{
|
||||
unsafe fn get_unchecked(&mut self, i: usize) -> I::Item {
|
||||
match self.iter {
|
||||
Some(ref mut iter) => iter.get_unchecked(i),
|
||||
// SAFETY: the caller asserts there is an item at `i`, so we're not exhausted.
|
||||
None => intrinsics::unreachable(),
|
||||
}
|
||||
}
|
||||
|
||||
fn may_have_side_effect() -> bool {
|
||||
I::may_have_side_effect()
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue