execute method
Implementation
Future<bool> execute(Observable? observable) async {
bool ok = true;
if (observable == null) return ok;
// get expression
String? expression = (observable.isEval)
? observable.value
: (observable.signature ?? observable.value);
if (isNullOrEmpty(expression)) return ok;
// replace 'this' pointer with the parent model id
if (expression!.contains(thisDot)) {
expression = expression.replaceAll(thisDot, "${model.id}.");
}
// get variables from observable
Map<String, dynamic> variables = observable.getVariables();
// execute the expression
return executeExpression(expression, variables);
}