parseTime function
Implementation
DateTime parseTime(String value) {
if (value.isEmpty) {
throw "Empty string";
}
if (!RegExp(r"^\d{1,2}:\d{1,2}$").hasMatch(value)) {
throw "Invalid time format. Must be hh:mm";
}
var tokens = value.split(":");
return DateTime(int.parse(tokens[0]), int.parse(tokens[1]));
}