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// Copyright 2021 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 a
// SliceEqual reports whether two slices are equal: the same length and all
// elements equal. All floating point NaNs are considered equal.
func SliceEqual[Elem comparable](s1, s2 []Elem) bool {
if len(s1) != len(s2) {
return false
}
for i, v1 := range s1 {
v2 := s2[i]
if v1 != v2 {
isNaN := func(f Elem) bool { return f != f }
if !isNaN(v1) || !isNaN(v2) {
return false
}
}
}
return true
}
// Keys returns the keys of the map m.
// The keys will be an indeterminate order.
func Keys[K comparable, V any](m map[K]V) []K {
r := make([]K, 0, len(m))
for k := range m {
r = append(r, k)
}
return r
}
// Values returns the values of the map m.
// The values will be in an indeterminate order.
func Values[K comparable, V any](m map[K]V) []V {
r := make([]V, 0, len(m))
for _, v := range m {
r = append(r, v)
}
return r
}
// Equal reports whether two maps contain the same key/value pairs.
// Values are compared using ==.
func Equal[K, V comparable](m1, m2 map[K]V) bool {
if len(m1) != len(m2) {
return false
}
for k, v1 := range m1 {
if v2, ok := m2[k]; !ok || v1 != v2 {
return false
}
}
return true
}
// Copy returns a copy of m.
func Copy[K comparable, V any](m map[K]V) map[K]V {
r := make(map[K]V, len(m))
for k, v := range m {
r[k] = v
}
return r
}
// Add adds all key/value pairs in m2 to m1. Keys in m2 that are already
// present in m1 will be overwritten with the value in m2.
func Add[K comparable, V any](m1, m2 map[K]V) {
for k, v := range m2 {
m1[k] = v
}
}
// Sub removes all keys in m2 from m1. Keys in m2 that are not present
// in m1 are ignored. The values in m2 are ignored.
func Sub[K comparable, V any](m1, m2 map[K]V) {
for k := range m2 {
delete(m1, k)
}
}
// Intersect removes all keys from m1 that are not present in m2.
// Keys in m2 that are not in m1 are ignored. The values in m2 are ignored.
func Intersect[K comparable, V any](m1, m2 map[K]V) {
for k := range m1 {
if _, ok := m2[k]; !ok {
delete(m1, k)
}
}
}
// Filter deletes any key/value pairs from m for which f returns false.
func Filter[K comparable, V any](m map[K]V, f func(K, V) bool) {
for k, v := range m {
if !f(k, v) {
delete(m, k)
}
}
}
// TransformValues applies f to each value in m. The keys remain unchanged.
func TransformValues[K comparable, V any](m map[K]V, f func(V) V) {
for k, v := range m {
m[k] = f(v)
}
}
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