process method

@override ProcessedArg process(JsonWidgetRegistry registry, dynamic arg, Set<String>? listenVariables)

Process passed arg into ProcessedArg. The registry is giving functions and variables information context for the processing.

Passed listenVariables is the information about variables that JsonWidgetData depends on. Passing that should be make the ArgProcessor to stop calculating these variable names. It is treated as a optimization.

ProcessedArg contains info about arg real value and variable names that it depends on.

Implementation

@override
ProcessedArg process(
  JsonWidgetRegistry registry,
  dynamic arg,
  Set<String>? listenVariables,
) {
  var calculateListenVariables = listenVariables == null;
  var resultListenVariables = listenVariables ?? <String>{};

  var regexpMatch = _matchRegexp.firstMatch(arg.toString())!;
  var expression = Expression.tryParse(regexpMatch.group(1)!);
  if (expression != null) {
    var evaluator =
        ArgsExpressionEvaluator(registry, calculateListenVariables);
    arg = evaluator.evaluate(expression);
    if (calculateListenVariables) {
      resultListenVariables = evaluator.listenVariables;
    }
  }
  return ProcessedArg(
    listenVariables: resultListenVariables,
    value: arg,
  );
}