diff --git a/format/desktop_entry/error.ha b/format/desktop_entry/error.ha
index f3c2b73..0e46951 100644
--- a/format/desktop_entry/error.ha
+++ b/format/desktop_entry/error.ha
@@ -1,28 +1,27 @@
 // Any error which may be returned from a function in this module.
-export type error = !enum {
-	INVALID_GROUP_HEADER,
-	INVALID_ENTRY,
-	// unused for now
-	  DUPLICATE_GROUP,
-	  DUPLICATE_ENTRY,
-	  DUPLICATE_LOCALIZATION,
-	  NO_DEFAULT_VALUE,
-	  ENTRY_OUTSIDE_GROUP,
-	// --------------
-	UNSUPPORTED_ESCAPE,
-	STRING_NOT_ASCII,
-};
+export type error = !(
+	invalid_group_header |
+	invalid_entry |
+	invalid_ascii |
+	invalid_escape);
+
+// Returned when a malformed group header is encountered while parsing.
+export type invalid_group_header = !void;
+
+// Returned when a malformed entry is encountered while parsing.
+export type invalid_entry = !void;
+
+// Returned when ASCII text was expected, while parsing, but something else was
+// given.
+export type invalid_ascii = !void;
+
+// Returned when an invalid escape sequence was enctountered while parsing.
+export type invalid_escape = !void;
 
 // Converts a desktop entry [[error]] into a user-friendly string.
-export fn strerror(err: error) str = switch {
-case INVALID_GROUP_HEADER       => yield "invalid group header";
-case INVALID_ENTRY              => yield "invalid entry";
-case DUPLICATE_GROUP            => yield "duplicate group";
-case DUPLICATE_ENTRY            => yield "duplicate entry";
-case DUPLICATE_LOCALIZATION     => yield "duplicate localization";
-case NO_DEFAULT_VALUE           => yield "no default value";
-case ENTRY_OUTSIDE_GROUP        => yield "entry outside group";
-case UNSUPPORTED_ESCAPE         => yield "unsupported escape";
-case STRING_NOT_ASCII           => yield "string not ascii";
-case                            => yield "unknown";
+export fn strerror(err: error) str = match (err) {
+case invalid_group_header => yield "invalid group header";
+case invalid_entry        => yield "invalid entry";
+case invalid_ascii        => yield "invalid ascii";
+case invalid_escape       => yield "invalid escape";
 };