Fix some more Resolver changes.

kong.go

@@ -43,7 +43,7 @@ type Kong struct {
 	Stderr io.Writer
 
 	bindings  bindings
-	loader    ConfigurationFunc
+	loader    ConfigurationLoader
 	resolvers []Resolver
 	registry  *Registry
 
@@ -332,7 +332,7 @@ func (k *Kong) FatalIfErrorf(err error, args ...interface{}) {
 // LoadConfig from path using the loader configured via Configuration(loader).
 //
 // "path" will have ~/ expanded.
-func (k *Kong) LoadConfig(path string) (ResolverFunc, error) {
+func (k *Kong) LoadConfig(path string) (Resolver, error) {
 	path = expandPath(path)
 	r, err := os.Open(path) // nolint: gas
 	if err != nil {

options.go

@@ -188,17 +188,17 @@ func Resolvers(resolvers ...Resolver) OptionFunc {
 	}
 }
 
-// ConfigurationFunc is a function that builds a resolver from a file.
-type ConfigurationFunc func(r io.Reader) (ResolverFunc, error)
+// ConfigurationLoader is a function that builds a resolver from a file.
+type ConfigurationLoader func(r io.Reader) (Resolver, error)
 
 // Configuration provides Kong with support for loading defaults from a set of configuration files.
 //
-// Paths will be opened in order, and "loader" will be used to provide a ResolverFunc which is registered with Kong.
+// Paths will be opened in order, and "loader" will be used to provide a Resolver which is registered with Kong.
 //
-// Note: The JSON function is a ConfigurationFunc.
+// Note: The JSON function is a ConfigurationLoader.
 //
 // ~ expansion will occur on the provided paths.
-func Configuration(loader ConfigurationFunc, paths ...string) OptionFunc {
+func Configuration(loader ConfigurationLoader, paths ...string) OptionFunc {
 	return func(k *Kong) error {
 		k.loader = loader
 		for _, path := range paths {

resolver.go

@@ -31,13 +31,13 @@ func (r ResolverFunc) Validate(app *Application) error { return nil } //  nolint
 // JSON returns a Resolver that retrieves values from a JSON source.
 //
 // Hyphens in flag names are replaced with underscores.
-func JSON(r io.Reader) (ResolverFunc, error) {
+func JSON(r io.Reader) (Resolver, error) {
 	values := map[string]interface{}{}
 	err := json.NewDecoder(r).Decode(&values)
 	if err != nil {
 		return nil, err
 	}
-	f := func(context *Context, parent *Path, flag *Flag) (string, error) {
+	var f ResolverFunc = func(context *Context, parent *Path, flag *Flag) (string, error) {
 		name := strings.Replace(flag.Name, "-", "_", -1)
 		raw, ok := values[name]
 		if !ok {