github.com/goproxy0/go@v0.0.0-20171111080102-49cc0c489d2c/src/sort/slice.go (about)

     1  // Copyright 2017 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build !compiler_bootstrap go1.8
     6  
     7  package sort
     8  
     9  import "reflect"
    10  
    11  // Slice sorts the provided slice given the provided less function.
    12  //
    13  // The sort is not guaranteed to be stable. For a stable sort, use
    14  // SliceStable.
    15  //
    16  // The function panics if the provided interface is not a slice.
    17  func Slice(slice interface{}, less func(i, j int) bool) {
    18  	rv := reflect.ValueOf(slice)
    19  	swap := reflect.Swapper(slice)
    20  	length := rv.Len()
    21  	quickSort_func(lessSwap{less, swap}, 0, length, maxDepth(length))
    22  }
    23  
    24  // SliceStable sorts the provided slice given the provided less
    25  // function while keeping the original order of equal elements.
    26  //
    27  // The function panics if the provided interface is not a slice.
    28  func SliceStable(slice interface{}, less func(i, j int) bool) {
    29  	rv := reflect.ValueOf(slice)
    30  	swap := reflect.Swapper(slice)
    31  	stable_func(lessSwap{less, swap}, rv.Len())
    32  }
    33  
    34  // SliceIsSorted tests whether a slice is sorted.
    35  //
    36  // The function panics if the provided interface is not a slice.
    37  func SliceIsSorted(slice interface{}, less func(i, j int) bool) bool {
    38  	rv := reflect.ValueOf(slice)
    39  	n := rv.Len()
    40  	for i := n - 1; i > 0; i-- {
    41  		if less(i, i-1) {
    42  			return false
    43  		}
    44  	}
    45  	return true
    46  }