Result is failed by default

TODO.txt

@@ -1,4 +1,3 @@
-Result should be Failed by default
 Test RuneReader
 Test Regexp
 Add SPDX tags

gigaparsec.go

@@ -10,7 +10,7 @@ import (
 )
 
 type Result[In, Out any] struct {
-	consumed, failed bool
+	consumed, succeeded bool
 	value               Out
 	next                State[In]
 	message             Message
@@ -19,14 +19,14 @@ type Result[In, Out any] struct {
 func Fail[In, Out any](consumed bool, msg Message) Result[In, Out] {
 	return Result[In, Out]{
 		consumed:  consumed,
-		failed:   true,
+		succeeded: false,
 		message:   msg,
 	}
 }
 
-func (r Result[In, Out]) Failed() (ok, consumed bool, msg Message) {
-	ok = r.failed
-	if ok {
+func (r Result[In, Out]) Failed() (failed, consumed bool, msg Message) {
+	failed = !r.succeeded
+	if failed {
 		consumed = r.consumed
 		msg = r.message
 	}
@@ -35,7 +35,7 @@ func (r Result[In, Out]) Failed() (ok, consumed bool, msg Message) {
 
 func Succeed[In, Out any](consumed bool, value Out, next State[In], msg Message) Result[In, Out] {
 	return Result[In, Out]{
-		failed:   false,
+		succeeded: true,
 		value:     value,
 		consumed:  consumed,
 		next:      next,
@@ -43,9 +43,9 @@ func Succeed[In, Out any](consumed bool, value Out, next State[In], msg Message)
 	}
 }
 
-func (r Result[In, Out]) Succeeded() (ok, consumed bool, value Out, next State[In], msg Message) {
-	ok = !r.failed
-	if ok {
+func (r Result[In, Out]) Succeeded() (succeeded, consumed bool, value Out, next State[In], msg Message) {
+	succeeded = r.succeeded
+	if succeeded {
 		consumed = r.consumed
 		value = r.value
 		next = r.next

parser_test.go

@@ -56,8 +56,10 @@ func TestSlice(t *testing.T) {
 		r := ptest.ErrReaderAt(expectedErr)
 		c := cursor.NewReaderAt(r)
 		s := rapid.SliceOfN(rapid.Byte(), 0, 100).Draw(t, "s")
-		_, err := gigaparsec.Slice(s)(gigaparsec.MakeState(c))
+		result, err := gigaparsec.Slice(s)(gigaparsec.MakeState(c))
+		failed, _, _ := result.Failed()
 		test.ErrorIs(t, err, expectedErr)
+		test.True(t, failed)
 	}))
 	t.Run("succeeds when contents match", rapid.MakeCheck(func(t *rapid.T) {
 		input := rapid.SliceOfN(rapid.Byte(), 1, -1).Draw(t, "input")