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// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package sort
import (
"internal/reflectlite"
"math/bits"
)
// Slice sorts the slice x given the provided less function.
// It panics if x is not a slice.
//
// The sort is not guaranteed to be stable: equal elements
// may be reversed from their original order.
// For a stable sort, use [SliceStable].
//
// The less function must satisfy the same requirements as
// the Interface type's Less method.
//
// Note: in many situations, the newer [slices.SortFunc] function is more
// ergonomic and runs faster.
func Slice(x any, less func(i, j int) bool) {
rv := reflectlite.ValueOf(x)
swap := reflectlite.Swapper(x)
length := rv.Len()
limit := bits.Len(uint(length))
pdqsort_func(lessSwap{less, swap}, 0, length, limit)
}
// SliceStable sorts the slice x using the provided less
// function, keeping equal elements in their original order.
// It panics if x is not a slice.
//
// The less function must satisfy the same requirements as
// the Interface type's Less method.
//
// Note: in many situations, the newer [slices.SortStableFunc] function is more
// ergonomic and runs faster.
func SliceStable(x any, less func(i, j int) bool) {
rv := reflectlite.ValueOf(x)
swap := reflectlite.Swapper(x)
stable_func(lessSwap{less, swap}, rv.Len())
}
// SliceIsSorted reports whether the slice x is sorted according to the provided less function.
// It panics if x is not a slice.
//
// Note: in many situations, the newer [slices.IsSortedFunc] function is more
// ergonomic and runs faster.
func SliceIsSorted(x any, less func(i, j int) bool) bool {
rv := reflectlite.ValueOf(x)
n := rv.Len()
for i := n - 1; i > 0; i-- {
if less(i, i-1) {
return false
}
}
return true
}