asDigit method
- String char
Turn char
into a number representing a digit, or null if it doesn't
represent a digit in this locale.
Implementation
int? asDigit(String char) {
var charCode = char.codeUnitAt(0);
var digitValue = charCode - _localeZero;
if (digitValue >= 0 && digitValue < 10) {
return digitValue;
} else {
return null;
}
}