fromString static method
Implementation
static Coin fromString(String str) {
final String coinRegex = r"/^(-?[0-9]+(\\.[0-9]+)?)([0-9a-zA-Z/]+)$/";
bool m = RegExp(coinRegex).hasMatch(str);
if (!m) {
throw Exception("failed to parse to Coin: $str");
}
var amount = double.parse(str[1]);
var denom = str[3];
return Coin(denom, amount);
}