github.com/linchen2chris/hugo@v0.0.0-20230307053224-cec209389705/common/types/types.go (about)

     1  // Copyright 2019 The Hugo Authors. All rights reserved.
     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  // http://www.apache.org/licenses/LICENSE-2.0
     7  //
     8  // Unless required by applicable law or agreed to in writing, software
     9  // distributed under the License is distributed on an "AS IS" BASIS,
    10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  // Package types contains types shared between packages in Hugo.
    15  package types
    16  
    17  import (
    18  	"fmt"
    19  	"reflect"
    20  
    21  	"github.com/spf13/cast"
    22  )
    23  
    24  // RLocker represents the read locks in sync.RWMutex.
    25  type RLocker interface {
    26  	RLock()
    27  	RUnlock()
    28  }
    29  
    30  // KeyValue is a interface{} tuple.
    31  type KeyValue struct {
    32  	Key   any
    33  	Value any
    34  }
    35  
    36  // KeyValueStr is a string tuple.
    37  type KeyValueStr struct {
    38  	Key   string
    39  	Value string
    40  }
    41  
    42  // KeyValues holds an key and a slice of values.
    43  type KeyValues struct {
    44  	Key    any
    45  	Values []any
    46  }
    47  
    48  // KeyString returns the key as a string, an empty string if conversion fails.
    49  func (k KeyValues) KeyString() string {
    50  	return cast.ToString(k.Key)
    51  }
    52  
    53  func (k KeyValues) String() string {
    54  	return fmt.Sprintf("%v: %v", k.Key, k.Values)
    55  }
    56  
    57  // NewKeyValuesStrings takes a given key and slice of values and returns a new
    58  // KeyValues struct.
    59  func NewKeyValuesStrings(key string, values ...string) KeyValues {
    60  	iv := make([]any, len(values))
    61  	for i := 0; i < len(values); i++ {
    62  		iv[i] = values[i]
    63  	}
    64  	return KeyValues{Key: key, Values: iv}
    65  }
    66  
    67  // Zeroer, as implemented by time.Time, will be used by the truth template
    68  // funcs in Hugo (if, with, not, and, or).
    69  type Zeroer interface {
    70  	IsZero() bool
    71  }
    72  
    73  // IsNil reports whether v is nil.
    74  func IsNil(v any) bool {
    75  	if v == nil {
    76  		return true
    77  	}
    78  
    79  	value := reflect.ValueOf(v)
    80  	switch value.Kind() {
    81  	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
    82  		return value.IsNil()
    83  	}
    84  
    85  	return false
    86  }
    87  
    88  // DevMarker is a marker interface for types that should only be used during
    89  // development.
    90  type DevMarker interface {
    91  	DevOnly()
    92  }