Populate tag name customization

bind.go

@@ -361,7 +361,11 @@ func (b bind) bind(fs FlagSet, v interface{}) (err error) {
 		// short name.
 		if !tag.HasExplicitName ||
 			(usePFlag && tag.Name == tag.ShortName) {
-			tag.Name = FromCamelCase(structField.Name, Separator)
+			if b.NamePopulator == nil {
+				tag.Name = FromCamelCase(structField.Name, Separator)
+			} else {
+				tag.Name = b.NamePopulator(structField.Name)
+			}
 		}
 
 		fieldV := val.Field(i)

option.go

@@ -11,6 +11,7 @@ func newBind(opts ...Option) bind {
 type bind struct {
 	Prefix        string
 	NoAutoFlatten bool
+	NamePopulator func(fieldName string) string
 }
 
 func (b bind) Option() Option {
@@ -41,3 +42,9 @@ func NoAutoFlatten() Option {
 		b.NoAutoFlatten = true
 	}
 }
+
+func NamePopulator(fn func(fieldName string) string) Option {
+	return func(b *bind) {
+		b.NamePopulator = fn
+	}
+}