How to check the rendering of RTB advertising Yandex?

Good morning.
Yandex is the Callback function onRender, which is called after the rendering of advertising.
Something I don't know how to check that the rendering did not happen.

For example:
onRender: function(data) {
// Something

And then somewhere on the page, check that "something" and if that is empty then execute your code.
April 3rd 20 at 17:14
1 answer
April 3rd 20 at 17:16
This can be done by means of the code of Yandex, a direct link to the paragraph about it:
It's not quite what I need.
When should AdBlock, it zablocie whole kotovasiya :)
There are alternatives to testing it, but wanted to try to do it using onRender
Just wondering, is it possible and how to do it:
onRender: function(data) {
// Here put variable or any record that could be checked in another script?
// For example var a=1, but it is not remembered.
// And somewhere below checking if a!=1, so is not pictured (bloknuli it or not found it), run something else
- Tod.Donnelly86 commented on April 3rd 20 at 17:19

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