94 lines
2.3 KiB
Rust
94 lines
2.3 KiB
Rust
use core::fmt::{self, Debug, Display};
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use core::cmp::Ordering;
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#[derive(Clone, Copy, Debug, Hash)]
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pub enum Length {
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Unbounded,
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Bounded(usize),
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}
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impl Length {
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pub fn try_len(&self) -> Option<usize> {
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match *self {
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Length::Unbounded => None,
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Length::Bounded(n) => Some(n),
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}
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}
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pub unsafe fn len(&self) -> usize {
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match *self {
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Length::Unbounded => {
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panic!("attempt to convert `Length::Unbounded` to `usize`")
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}
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Length::Bounded(n) => n,
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}
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}
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pub fn is_bounded(&self) -> bool {
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match *self {
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Length::Unbounded => false,
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Length::Bounded(_) => true,
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}
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}
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}
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impl Display for Length {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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Debug::fmt(self, f)
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}
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}
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impl PartialEq for Length {
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fn eq(&self, rhs: &Length) -> bool {
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match (*self, *rhs) {
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(Length::Unbounded, _) => false,
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(_, Length::Unbounded) => false,
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(Length::Bounded(a), Length::Bounded(ref b)) => a.eq(b),
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}
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}
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fn ne(&self, rhs: &Length) -> bool {
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match (*self, *rhs) {
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(Length::Unbounded, _) => false,
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(_, Length::Unbounded) => false,
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(Length::Bounded(a), Length::Bounded(ref b)) => a.ne(b),
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}
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}
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}
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impl PartialEq<usize> for Length {
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fn eq(&self, rhs: &usize) -> bool {
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match *self {
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Length::Unbounded => false,
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Length::Bounded(n) => n.eq(rhs),
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}
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}
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fn ne(&self, rhs: &usize) -> bool {
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match *self {
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Length::Unbounded => false,
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Length::Bounded(n) => n.eq(rhs),
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}
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}
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}
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impl PartialOrd for Length {
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fn partial_cmp(&self, rhs: &Length) -> Option<Ordering> {
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match (*self, *rhs) {
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(Length::Unbounded, Length::Unbounded) => None,
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(Length::Unbounded, _) => Some(Ordering::Greater),
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(_, Length::Unbounded) => Some(Ordering::Less),
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(Length::Bounded(a), Length::Bounded(ref b)) => a.partial_cmp(b),
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}
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}
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}
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impl PartialOrd<usize> for Length {
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fn partial_cmp(&self, rhs: &usize) -> Option<Ordering> {
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match *self {
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Length::Unbounded => Some(Ordering::Greater),
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Length::Bounded(n) => n.partial_cmp(rhs),
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}
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}
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}
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