OpenE2K
/
rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Manually fuse the inner iterator in FlattenCompat

This commit is contained in:
Giacomo Stevanato 2021-01-23 21:00:00 +01:00
parent f241c10223
commit 5aa625b903
1 changed files with 14 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
library/core/src/iter/adapters/flatten.rs
View File

@ -265,7 +265,13 @@ where
}
}
match self.iter.next() {
None => return self.backiter.as_mut()?.next(),
None => match self.backiter.as_mut()?.next() {
None => {
self.backiter = None;
return None;
}
elt @ Some(_) => return elt,
},
Some(inner) => self.frontiter = Some(inner.into_iter()),
}
}
@ -353,7 +359,13 @@ where
}
}
match self.iter.next_back() {
None => return self.frontiter.as_mut()?.next_back(),
None => match self.frontiter.as_mut()?.next_back() {
None => {
self.frontiter = None;
return None;
}
elt @ Some(_) => return elt,
},
next => self.backiter = next.map(IntoIterator::into_iter),
}
}