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#[cfg(test)]
mod tests;
#[derive(Clone, Hash, Debug, PartialEq)]
pub struct TinyList<T: PartialEq> {
head: Option<Element<T>>
}
impl<T: PartialEq> TinyList<T> {
#[inline]
pub fn new() -> TinyList<T> {
TinyList {
head: None
}
}
#[inline]
pub fn new_single(data: T) -> TinyList<T> {
TinyList {
head: Some(Element {
data,
next: None,
})
}
}
#[inline]
pub fn insert(&mut self, data: T) {
self.head = Some(Element {
data,
next: self.head.take().map(Box::new)
});
}
#[inline]
pub fn remove(&mut self, data: &T) -> bool {
self.head = match self.head {
Some(ref mut head) if head.data == *data => {
head.next.take().map(|x| *x)
}
Some(ref mut head) => return head.remove_next(data),
None => return false,
};
true
}
#[inline]
pub fn contains(&self, data: &T) -> bool {
let mut elem = self.head.as_ref();
while let Some(ref e) = elem {
if &e.data == data {
return true;
}
elem = e.next.as_ref().map(|e| &**e);
}
false
}
#[inline]
pub fn len(&self) -> usize {
let (mut elem, mut count) = (self.head.as_ref(), 0);
while let Some(ref e) = elem {
count += 1;
elem = e.next.as_ref().map(|e| &**e);
}
count
}
}
#[derive(Clone, Hash, Debug, PartialEq)]
struct Element<T: PartialEq> {
data: T,
next: Option<Box<Element<T>>>,
}
impl<T: PartialEq> Element<T> {
fn remove_next(&mut self, data: &T) -> bool {
let new_next = match self.next {
Some(ref mut next) if next.data == *data => next.next.take(),
Some(ref mut next) => return next.remove_next(data),
None => return false,
};
self.next = new_next;
true
}
}