src/evaluator/dataCommands.js
function jsonCommand(shell, args, data, evaluationId) {
  return dataCommand(shell, args, data, evaluationId, function(value) {
    return JSON.parse(value);
  });
}
function jsonCommand(shell, args, data, evaluationId) {
  return dataCommand(shell, args, data, evaluationId, function(value) {
    return JSON.parse(value);
  });
}
Implements the %%json command. This command can be used to initialize a variable containing a plain old javascript object parsed from JSON text.