Generalise post-build options.

kong.go

@@ -41,9 +41,8 @@ type Kong struct {
 	noDefaultHelp bool
 	help          func(*Context) error
 
-	// Set temporarily by Options. These are moved into the Model after build().
+	// Set temporarily by Options. These are applied after build().
-	name        string
+	postBuildOptions []Option
-	description string
 }
 
 // New creates a new Kong parser on grammar.
@@ -67,16 +66,13 @@ func New(grammar interface{}, options ...Option) (*Kong, error) {
 	if err != nil {
 		return k, err
 	}
-	if k.name == "" {
+	model.Name = filepath.Base(os.Args[0])
-		model.Name = filepath.Base(os.Args[0])
-	} else {
-		model.Name = k.name
-	}
-	if k.description != "" {
-		model.Help = k.description
-	}
 	k.Model = model
 
+	for _, option := range k.postBuildOptions {
+		option(k)
+	}
+
 	return k, nil
 }
 

options.go

@@ -23,7 +23,18 @@ func NoDefaultHelp() Option {
 // Name overrides the application name.
 func Name(name string) Option {
 	return func(k *Kong) {
-		k.name = name
+		k.postBuildOptions = append(k.postBuildOptions, func(k *Kong) {
+			k.Model.Name = name
+		})
+	}
+}
+
+// Description sets the application description.
+func Description(description string) Option {
+	return func(k *Kong) {
+		k.postBuildOptions = append(k.postBuildOptions, func(k *Kong) {
+			k.Model.Help = description
+		})
 	}
 }
 
@@ -47,13 +58,6 @@ func NamedMapper(name string, mapper Mapper) Option {
 	return func(k *Kong) { k.registry.RegisterName(name, mapper) }
 }
 
-// Description sets the application description.
-func Description(description string) Option {
-	return func(k *Kong) {
-		k.description = description
-	}
-}
-
 // Writers overrides the default writers. Useful for testing or interactive use.
 func Writers(stdout, stderr io.Writer) Option {
 	return func(k *Kong) {