tea/vendor/github.com/emirpasic/gods/utils/comparator.go

252 lines
4.8 KiB
Go

// Copyright (c) 2015, Emir Pasic. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package utils
import "time"
// Comparator will make type assertion (see IntComparator for example),
// which will panic if a or b are not of the asserted type.
//
// Should return a number:
// negative , if a < b
// zero , if a == b
// positive , if a > b
type Comparator func(a, b interface{}) int
// StringComparator provides a fast comparison on strings
func StringComparator(a, b interface{}) int {
s1 := a.(string)
s2 := b.(string)
min := len(s2)
if len(s1) < len(s2) {
min = len(s1)
}
diff := 0
for i := 0; i < min && diff == 0; i++ {
diff = int(s1[i]) - int(s2[i])
}
if diff == 0 {
diff = len(s1) - len(s2)
}
if diff < 0 {
return -1
}
if diff > 0 {
return 1
}
return 0
}
// IntComparator provides a basic comparison on int
func IntComparator(a, b interface{}) int {
aAsserted := a.(int)
bAsserted := b.(int)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// Int8Comparator provides a basic comparison on int8
func Int8Comparator(a, b interface{}) int {
aAsserted := a.(int8)
bAsserted := b.(int8)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// Int16Comparator provides a basic comparison on int16
func Int16Comparator(a, b interface{}) int {
aAsserted := a.(int16)
bAsserted := b.(int16)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// Int32Comparator provides a basic comparison on int32
func Int32Comparator(a, b interface{}) int {
aAsserted := a.(int32)
bAsserted := b.(int32)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// Int64Comparator provides a basic comparison on int64
func Int64Comparator(a, b interface{}) int {
aAsserted := a.(int64)
bAsserted := b.(int64)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// UIntComparator provides a basic comparison on uint
func UIntComparator(a, b interface{}) int {
aAsserted := a.(uint)
bAsserted := b.(uint)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// UInt8Comparator provides a basic comparison on uint8
func UInt8Comparator(a, b interface{}) int {
aAsserted := a.(uint8)
bAsserted := b.(uint8)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// UInt16Comparator provides a basic comparison on uint16
func UInt16Comparator(a, b interface{}) int {
aAsserted := a.(uint16)
bAsserted := b.(uint16)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// UInt32Comparator provides a basic comparison on uint32
func UInt32Comparator(a, b interface{}) int {
aAsserted := a.(uint32)
bAsserted := b.(uint32)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// UInt64Comparator provides a basic comparison on uint64
func UInt64Comparator(a, b interface{}) int {
aAsserted := a.(uint64)
bAsserted := b.(uint64)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// Float32Comparator provides a basic comparison on float32
func Float32Comparator(a, b interface{}) int {
aAsserted := a.(float32)
bAsserted := b.(float32)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// Float64Comparator provides a basic comparison on float64
func Float64Comparator(a, b interface{}) int {
aAsserted := a.(float64)
bAsserted := b.(float64)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// ByteComparator provides a basic comparison on byte
func ByteComparator(a, b interface{}) int {
aAsserted := a.(byte)
bAsserted := b.(byte)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// RuneComparator provides a basic comparison on rune
func RuneComparator(a, b interface{}) int {
aAsserted := a.(rune)
bAsserted := b.(rune)
switch {
case aAsserted > bAsserted:
return 1
case aAsserted < bAsserted:
return -1
default:
return 0
}
}
// TimeComparator provides a basic comparison on time.Time
func TimeComparator(a, b interface{}) int {
aAsserted := a.(time.Time)
bAsserted := b.(time.Time)
switch {
case aAsserted.After(bAsserted):
return 1
case aAsserted.Before(bAsserted):
return -1
default:
return 0
}
}