github.com/kaydxh/golang@v0.0.131/pkg/config/config_option.go (about) 1 /* 2 *Copyright (c) 2022, kaydxh 3 * 4 *Permission is hereby granted, free of charge, to any person obtaining a copy 5 *of this software and associated documentation files (the "Software"), to deal 6 *in the Software without restriction, including without limitation the rights 7 *to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 8 *copies of the Software, and to permit persons to whom the Software is 9 *furnished to do so, subject to the following conditions: 10 * 11 *The above copyright notice and this permission notice shall be included in all 12 *copies or substantial portions of the Software. 13 * 14 *THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 *IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 *FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 17 *AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 18 *LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 19 *OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 20 *SOFTWARE. 21 */ 22 package config 23 24 import "google.golang.org/protobuf/proto" 25 26 // A ConfigOption sets options. 27 type ConfigOption[T proto.Message] interface { 28 apply(*Config[T]) 29 } 30 31 // EmptyConfigOption does not alter the configuration. It can be embedded 32 // in another structure to build custom options. 33 // 34 // This API is EXPERIMENTAL. 35 type EmptyConfigOption[T proto.Message] struct{} 36 37 func (EmptyConfigOption[T]) apply(*Config[T]) {} 38 39 // ConfigOptionFunc wraps a function that modifies Client into an 40 // implementation of the ConfigOption interface. 41 type ConfigOptionFunc[T proto.Message] func(*Config[T]) 42 43 func (f ConfigOptionFunc[T]) apply(do *Config[T]) { 44 f(do) 45 } 46 47 // sample code for option, default for nothing to change 48 func _ConfigOptionWithDefault[T proto.Message]() ConfigOption[T] { 49 return ConfigOptionFunc[T](func(*Config[T]) { 50 // nothing to change 51 }) 52 } 53 func (o *Config[T]) ApplyOptions(options ...ConfigOption[T]) *Config[T] { 54 for _, opt := range options { 55 if opt == nil { 56 continue 57 } 58 opt.apply(o) 59 } 60 return o 61 }