diff options
Diffstat (limited to 'src/iter.rs')
-rw-r--r-- | src/iter.rs | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/src/iter.rs b/src/iter.rs new file mode 100644 index 0000000..702c653 --- /dev/null +++ b/src/iter.rs @@ -0,0 +1,46 @@ +use std::iter::Peekable; +use std::ops::Deref; + +pub struct Delimited<I: Iterator> { + is_first: bool, + iter: Peekable<I>, +} + +pub trait IterDelimited: Iterator + Sized { + fn delimited(self) -> Delimited<Self> { + Delimited { + is_first: true, + iter: self.peekable(), + } + } +} + +impl<I: Iterator> IterDelimited for I {} + +pub struct IteratorItem<T> { + value: T, + pub is_first: bool, + pub is_last: bool, +} + +impl<I: Iterator> Iterator for Delimited<I> { + type Item = IteratorItem<I::Item>; + + fn next(&mut self) -> Option<Self::Item> { + let item = IteratorItem { + value: self.iter.next()?, + is_first: self.is_first, + is_last: self.iter.peek().is_none(), + }; + self.is_first = false; + Some(item) + } +} + +impl<T> Deref for IteratorItem<T> { + type Target = T; + + fn deref(&self) -> &Self::Target { + &self.value + } +} |