toNum function
- IValidator child, {
- String? message,
Coerces a value to a number (num).
Handles existing numbers (num) and strings that can be parsed as a number.
Passes the resulting number to the child validator.
Implementation
IValidator toNum(IValidator child, {String? message}) {
final base = ($isNumber | $isNumString) &
core.transform(
(value) => switch (value) {
final num n => n,
final String s => num.tryParse(s.trim()),
_ => null,
},
child,
);
return handleReturnPreserveValue(base, message);
}