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Diffstat (limited to '')
-rw-r--r-- | vendor/indexmap/src/util.rs | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/vendor/indexmap/src/util.rs b/vendor/indexmap/src/util.rs new file mode 100644 index 0000000..377ff51 --- /dev/null +++ b/vendor/indexmap/src/util.rs @@ -0,0 +1,53 @@ +use core::ops::{Bound, Range, RangeBounds}; + +pub(crate) fn third<A, B, C>(t: (A, B, C)) -> C { + t.2 +} + +pub(crate) fn simplify_range<R>(range: R, len: usize) -> Range<usize> +where + R: RangeBounds<usize>, +{ + let start = match range.start_bound() { + Bound::Unbounded => 0, + Bound::Included(&i) if i <= len => i, + Bound::Excluded(&i) if i < len => i + 1, + bound => panic!("range start {:?} should be <= length {}", bound, len), + }; + let end = match range.end_bound() { + Bound::Unbounded => len, + Bound::Excluded(&i) if i <= len => i, + Bound::Included(&i) if i < len => i + 1, + bound => panic!("range end {:?} should be <= length {}", bound, len), + }; + if start > end { + panic!( + "range start {:?} should be <= range end {:?}", + range.start_bound(), + range.end_bound() + ); + } + start..end +} + +pub(crate) fn try_simplify_range<R>(range: R, len: usize) -> Option<Range<usize>> +where + R: RangeBounds<usize>, +{ + let start = match range.start_bound() { + Bound::Unbounded => 0, + Bound::Included(&i) if i <= len => i, + Bound::Excluded(&i) if i < len => i + 1, + _ => return None, + }; + let end = match range.end_bound() { + Bound::Unbounded => len, + Bound::Excluded(&i) if i <= len => i, + Bound::Included(&i) if i < len => i + 1, + _ => return None, + }; + if start > end { + return None; + } + Some(start..end) +} |