decode static method
Implementation
static UEpubPosition? decode(String? value) {
if (value == null || !value.startsWith("u-epub:")) return null;
final RegExpMatch? match = RegExp(r"^u-epub:(\d+)/(\d+):(\d+)$").firstMatch(value);
if (match == null) return null;
return UEpubPosition(
spineIndex: int.tryParse(match.group(1) ?? "0") ?? 0,
blockIndex: int.tryParse(match.group(2) ?? "0") ?? 0,
charOffset: int.tryParse(match.group(3) ?? "0") ?? 0,
);
}