github.com/coreos/mantle@v0.13.0/lang/maps/sorted.go (about)

     1  // Copyright 2016 CoreOS, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package maps
    16  
    17  import (
    18  	"reflect"
    19  	"sort"
    20  
    21  	"github.com/coreos/mantle/lang/natsort"
    22  )
    23  
    24  // Keys returns a map's keys as an unordered slice of strings.
    25  func Keys(m interface{}) []string {
    26  	mapValue := reflect.ValueOf(m)
    27  
    28  	// Value.String() isn't sufficient to assert the keys are strings.
    29  	if mapValue.Type().Key().Kind() != reflect.String {
    30  		panic("maps: keys must be strings")
    31  	}
    32  
    33  	keyValues := mapValue.MapKeys()
    34  	keys := make([]string, len(keyValues))
    35  	for i, k := range keyValues {
    36  		keys[i] = k.String()
    37  	}
    38  
    39  	return keys
    40  }
    41  
    42  // SortedKeys returns a map's keys as a sorted slice of strings.
    43  func SortedKeys(m interface{}) []string {
    44  	keys := Keys(m)
    45  	sort.Strings(keys)
    46  	return keys
    47  }
    48  
    49  // NaturalKeys returns a map's keys as a natural sorted slice of strings.
    50  // See github.com/coreos/mantle/lang/natsort
    51  func NaturalKeys(m interface{}) []string {
    52  	keys := Keys(m)
    53  	natsort.Strings(keys)
    54  	return keys
    55  }