ordered.go

/*
 * Copyright 2025 The Go-Spring Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package ordered

import (
	"cmp"
	"slices"
)

// MapKeys returns the sorted keys of a map whose key type is ordered.
// This provides a deterministic order for iteration over maps.
func MapKeys[M ~map[K]V, K cmp.Ordered, V any](m M) []K {
	r := make([]K, 0, len(m))
	for k := range m {
		r = append(r, k)
	}
	slices.Sort(r)
	return r
}