Don't require so much Pos() when making messages

bytes/regexp.go

@@ -70,14 +70,14 @@ func Regexp(pattern string) gigaparsec.Parser[byte, string] {
 		}
 		if idx == nil {
 			if err == io.EOF {
-				return gigaparsec.Fail[byte, string](false, gigaparsec.MessageEnd(input.Pos())), nil
+				return gigaparsec.Fail[byte, string](false, input.MessageOK()), nil
 			}
 			got := make([]byte, r.Count())
 			_, _, err = input.Read(got)
 			if err != nil {
 				return gigaparsec.Result[byte, string]{}, fmt.Errorf("Regexp: unexpected error: %w", err)
 			}
-			return gigaparsec.Fail[byte, string](false, gigaparsec.MakeMessage(input.Pos(), string(got), expected)), nil
+			return gigaparsec.Fail[byte, string](false, input.Message(string(got), expected)), nil
 		}
 		// Alas, this is a little wasteful because a Regexp can only return indices
 		// when searching a RuneReader.
@@ -87,7 +87,7 @@ func Regexp(pattern string) gigaparsec.Parser[byte, string] {
 			return gigaparsec.Result[byte, string]{}, fmt.Errorf("Regexp: unexpected error: %w", err)
 		}
 		next := input.At(input.Pos() + n)
-		return gigaparsec.Succeed(true, string(dst), next, gigaparsec.MessageOK(input.Pos())), nil
+		return gigaparsec.Succeed(true, string(dst), next, input.MessageOK()), nil
 	}
 }
 
@@ -98,14 +98,14 @@ func MatchString(s string) gigaparsec.Parser[byte, string] {
 		dst := make([]byte, len(s))
 		_, next, err := input.Read(dst)
 		if errors.Is(err, io.EOF) {
-			return gigaparsec.Fail[byte, string](false, gigaparsec.MessageEnd(input.Pos(), expected)), nil
+			return gigaparsec.Fail[byte, string](false, input.MessageEnd(expected)), nil
 		}
 		if err != nil {
 			return gigaparsec.Result[byte, string]{}, fmt.Errorf("MatchString: %w", err)
 		}
 		if !bytes.Equal(dst, b) {
-			return gigaparsec.Fail[byte, string](false, gigaparsec.MakeMessage(input.Pos(), string(dst), expected)), nil
+			return gigaparsec.Fail[byte, string](false, input.Message(string(dst), expected)), nil
 		}
-		return gigaparsec.Succeed(true, s, next, gigaparsec.MessageOK(input.Pos())), nil
+		return gigaparsec.Succeed(true, s, next, input.MessageOK()), nil
 	}
 }