safe-print.js

// We can't console.log inside of the event handlers since that triggers a new
// event source.  This is safe to call though, since it sets a global ignore flag.
var ignore = false;
function print(msg) {
  ignore = true;
  console.log(msg);
  ignore = false;
}

process.addAsyncListener(function () {
  if (ignore) return;
  // ...
}, {
  before: function (context, storage) {
    if (ignore || !storage) return;
    // ...
  },
  after: function (context, storage) {
    if (ignore || !storage) return;
    // ...
  }
});