1 // Copyright 2013-2022 Frank Schroeder. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4 5 package properties
6 7 import "flag"
8 9 // MustFlag sets flags that are skipped by dst.Parse when p contains
10 // the respective key for flag.Flag.Name.
11 //
12 // It's use is recommended with command line arguments as in:
13 //
14 // flag.Parse()
15 // p.MustFlag(flag.CommandLine)
16 func (p *Properties) MustFlag(dst *flag.FlagSet) {
17 m := make(map[string]*flag.Flag)
18 dst.VisitAll(func(f *flag.Flag) {
19 m[f.Name] = f
20 })
21 dst.Visit(func(f *flag.Flag) {
22 delete(m, f.Name) // overridden
23 })
24 25 for name, f := range m {
26 v, ok := p.Get(name)
27 if !ok {
28 continue
29 }
30 31 if err := f.Value.Set(v); err != nil {
32 ErrorHandler(err)
33 }
34 }
35 }
36