tryCall method
Implementation
FutureOr<R> tryCall(A a, B b, {TryCallOnError<R>? onError}) {
var f = this;
if (onError != null) {
try {
return f(a, b);
} catch (e, s) {
return onError(e, s);
}
} else {
return f(a, b);
}
}