@@ -6,12 +6,15 @@ type wobble struct {

 	Inception *wobble

 }

+// Fooer is an empty interface used for tests.

 type Fooer interface{}

+// Fooer2 is an interface used for tests.

 type Fooer2 interface {

 	Foo()

 }

+// Fooer3 is an interface used for tests.

 type Fooer3 interface {

 	Foo()

 	Bar(a string)

@@ -21,14 +24,17 @@ type Fooer3 interface {

 	Wiggle() (w wobble)

 }

+// Fooer4 is an interface used for tests.

 type Fooer4 interface {

 	Foo() error

 }

+// Bar is an interface used for tests.

 type Bar interface {

 	Boo(a string, b string) (s string, err error)

 }

+// Fooer5 is an interface used for tests.

 type Fooer5 interface {

 	Foo()

 	Bar

@@ -72,7 +72,7 @@ func main() {

 		InterfaceType string

 		RPCName       string

 		BuildTags     map[string]struct{}

-		*parsedPkg

+		*ParsedPkg

 	}{toLower(*typeName), *rpcName, flBuildTags.GetValues(), pkg}

 	var buf bytes.Buffer

@@ -9,18 +9,20 @@ import (

 	"reflect"

 )

-var ErrBadReturn = errors.New("found return arg with no name: all args must be named")

+var errBadReturn = errors.New("found return arg with no name: all args must be named")

-type ErrUnexpectedType struct {

+type errUnexpectedType struct {

 	expected string

 	actual   interface{}

 }

-func (e ErrUnexpectedType) Error() string {

+func (e errUnexpectedType) Error() string {

 	return fmt.Sprintf("got wrong type expecting %s, got: %v", e.expected, reflect.TypeOf(e.actual))

 }

-type parsedPkg struct {

+// ParsedPkg holds information about a package that has been parsed,

+// its name and the list of functions.

+type ParsedPkg struct {

 	Name      string

 	Functions []function

 }

@@ -41,14 +43,14 @@ func (a *arg) String() string {

 	return a.Name + " " + a.ArgType

 }

-// Parses the given file for an interface definition with the given name

-func Parse(filePath string, objName string) (*parsedPkg, error) {

+// Parse parses the given file for an interface definition with the given name.

+func Parse(filePath string, objName string) (*ParsedPkg, error) {

 	fs := token.NewFileSet()

 	pkg, err := parser.ParseFile(fs, filePath, nil, parser.AllErrors)

 	if err != nil {

 		return nil, err

 	}

-	p := &parsedPkg{}

+	p := &ParsedPkg{}

 	p.Name = pkg.Name.Name

 	obj, exists := pkg.Scope.Objects[objName]

 	if !exists {

@@ -59,11 +61,11 @@ func Parse(filePath string, objName string) (*parsedPkg, error) {

 	}

 	spec, ok := obj.Decl.(*ast.TypeSpec)

 	if !ok {

-		return nil, ErrUnexpectedType{"*ast.TypeSpec", obj.Decl}

+		return nil, errUnexpectedType{"*ast.TypeSpec", obj.Decl}

 	}

 	iface, ok := spec.Type.(*ast.InterfaceType)

 	if !ok {

-		return nil, ErrUnexpectedType{"*ast.InterfaceType", spec.Type}

+		return nil, errUnexpectedType{"*ast.InterfaceType", spec.Type}

 	}

 	p.Functions, err = parseInterface(iface)

@@ -90,11 +92,11 @@ func parseInterface(iface *ast.InterfaceType) ([]function, error) {

 		case *ast.Ident:

 			spec, ok := f.Obj.Decl.(*ast.TypeSpec)

 			if !ok {

-				return nil, ErrUnexpectedType{"*ast.TypeSpec", f.Obj.Decl}

+				return nil, errUnexpectedType{"*ast.TypeSpec", f.Obj.Decl}

 			}

 			iface, ok := spec.Type.(*ast.InterfaceType)

 			if !ok {

-				return nil, ErrUnexpectedType{"*ast.TypeSpec", spec.Type}

+				return nil, errUnexpectedType{"*ast.TypeSpec", spec.Type}

 			}

 			funcs, err := parseInterface(iface)

 			if err != nil {

@@ -103,7 +105,7 @@ func parseInterface(iface *ast.InterfaceType) ([]function, error) {

 			}

 			functions = append(functions, funcs...)

 		default:

-			return nil, ErrUnexpectedType{"*astFuncType or *ast.Ident", f}

+			return nil, errUnexpectedType{"*astFuncType or *ast.Ident", f}

 		}

 	}

 	return functions, nil

@@ -137,7 +139,7 @@ func parseArgs(fields []*ast.Field) ([]arg, error) {

 	var args []arg

 	for _, f := range fields {

 		if len(f.Names) == 0 {

-			return nil, ErrBadReturn

+			return nil, errBadReturn

 		}

 		for _, name := range f.Names {

 			var typeName string

@@ -147,11 +149,11 @@ func parseArgs(fields []*ast.Field) ([]arg, error) {

 			case *ast.StarExpr:

 				i, ok := argType.X.(*ast.Ident)

 				if !ok {

-					return nil, ErrUnexpectedType{"*ast.Ident", f.Type}

+					return nil, errUnexpectedType{"*ast.Ident", f.Type}

 				}

 				typeName = "*" + i.Name

 			default:

-				return nil, ErrUnexpectedType{"*ast.Ident or *ast.StarExpr", f.Type}

+				return nil, errUnexpectedType{"*ast.Ident or *ast.StarExpr", f.Type}

 			}

 			args = append(args, arg{name.Name, typeName})

@@ -22,7 +22,7 @@ func TestParseEmptyInterface(t *testing.T) {

 func TestParseNonInterfaceType(t *testing.T) {

 	_, err := Parse(testFixture, "wobble")

-	if _, ok := err.(ErrUnexpectedType); !ok {

+	if _, ok := err.(errUnexpectedType); !ok {

 		t.Fatal("expected type error when parsing non-interface type")

 	}

 }

@@ -109,7 +109,7 @@ func TestParseWithMultipleFuncs(t *testing.T) {

 func TestParseWithUnamedReturn(t *testing.T) {

 	_, err := Parse(testFixture, "Fooer4")

-	if !strings.HasSuffix(err.Error(), ErrBadReturn.Error()) {

+	if !strings.HasSuffix(err.Error(), errBadReturn.Error()) {

 		t.Fatalf("expected ErrBadReturn, got %v", err)

 	}

 }