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diff --git a/vendor/generic-array-0.12.4/src/functional.rs b/vendor/generic-array-0.12.4/src/functional.rs
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+//! Functional programming with generic sequences
+//!
+//! Please see `tests/generics.rs` for examples of how to best use these in your generic functions.
+
+use super::ArrayLength;
+use core::iter::FromIterator;
+use sequence::*;
+
+/// Defines the relationship between one generic sequence and another,
+/// for operations such as `map` and `zip`.
+pub unsafe trait MappedGenericSequence<T, U>: GenericSequence<T>
+where
+ Self::Length: ArrayLength<U>,
+{
+ /// Mapped sequence type
+ type Mapped: GenericSequence<U, Length = Self::Length>;
+}
+
+unsafe impl<'a, T, U, S: MappedGenericSequence<T, U>> MappedGenericSequence<T, U> for &'a S
+where
+ &'a S: GenericSequence<T>,
+ S: GenericSequence<T, Length = <&'a S as GenericSequence<T>>::Length>,
+ <S as GenericSequence<T>>::Length: ArrayLength<U>,
+{
+ type Mapped = <S as MappedGenericSequence<T, U>>::Mapped;
+}
+
+unsafe impl<'a, T, U, S: MappedGenericSequence<T, U>> MappedGenericSequence<T, U> for &'a mut S
+where
+ &'a mut S: GenericSequence<T>,
+ S: GenericSequence<T, Length = <&'a mut S as GenericSequence<T>>::Length>,
+ <S as GenericSequence<T>>::Length: ArrayLength<U>,
+{
+ type Mapped = <S as MappedGenericSequence<T, U>>::Mapped;
+}
+
+/// Accessor type for a mapped generic sequence
+pub type MappedSequence<S, T, U> =
+ <<S as MappedGenericSequence<T, U>>::Mapped as GenericSequence<U>>::Sequence;
+
+/// Defines functional programming methods for generic sequences
+pub unsafe trait FunctionalSequence<T>: GenericSequence<T> {
+ /// Maps a `GenericSequence` to another `GenericSequence`.
+ ///
+ /// If the mapping function panics, any already initialized elements in the new sequence
+ /// will be dropped, AND any unused elements in the source sequence will also be dropped.
+ fn map<U, F>(self, f: F) -> MappedSequence<Self, T, U>
+ where
+ Self: MappedGenericSequence<T, U>,
+ Self::Length: ArrayLength<U>,
+ F: FnMut(Self::Item) -> U,
+ {
+ FromIterator::from_iter(self.into_iter().map(f))
+ }
+
+ /// Combines two `GenericSequence` instances and iterates through both of them,
+ /// initializing a new `GenericSequence` with the result of the zipped mapping function.
+ ///
+ /// If the mapping function panics, any already initialized elements in the new sequence
+ /// will be dropped, AND any unused elements in the source sequences will also be dropped.
+ #[inline]
+ fn zip<B, Rhs, U, F>(self, rhs: Rhs, f: F) -> MappedSequence<Self, T, U>
+ where
+ Self: MappedGenericSequence<T, U>,
+ Rhs: MappedGenericSequence<B, U, Mapped = MappedSequence<Self, T, U>>,
+ Self::Length: ArrayLength<B> + ArrayLength<U>,
+ Rhs: GenericSequence<B, Length = Self::Length>,
+ F: FnMut(Self::Item, Rhs::Item) -> U,
+ {
+ rhs.inverted_zip2(self, f)
+ }
+
+ /// Folds (or reduces) a sequence of data into a single value.
+ ///
+ /// If the fold function panics, any unused elements will be dropped.
+ fn fold<U, F>(self, init: U, f: F) -> U
+ where
+ F: FnMut(U, Self::Item) -> U,
+ {
+ self.into_iter().fold(init, f)
+ }
+}
+
+unsafe impl<'a, T, S: GenericSequence<T>> FunctionalSequence<T> for &'a S
+where
+ &'a S: GenericSequence<T>,
+{
+}
+
+unsafe impl<'a, T, S: GenericSequence<T>> FunctionalSequence<T> for &'a mut S
+where
+ &'a mut S: GenericSequence<T>,
+{
+}