Is it possible to suppress the error "overlapping wildcard callback outputs"?

Dash Python
1

Dash version 2.17.0, Windows operating system.

Hello, I would like to suppress the error “overlapping wildcard callback outputs” in order to allow duplicate output across multiple pattern-matching callbacks.

Unfortunately, neither suppress_callback_exceptions=True nor allow_duplicate=True (in conjunction with prevent_initial_call=True) gets my app launched successfully.

I have distilled my app here to illustrate what I am trying to do in a bit more detail:

In general terms, my app will dynamically / on-the-fly instantiate pairs of dropdown/rangeslider and markdown components, which are associated by pattern-matching id. I have a MATCH-based callback that updates the markdown associated with a dropdown to show its currently selected value, and also a MATCH-based callback that updates the markdown associated with a rangeslider to show its currently selected value. This is working fine, but I also want another ALL-based callback that when triggered by a checkbox will update all markdown.

I thought this could work with allow_duplicate=True. But am I correct to conclude that Dash 2.17.0 does not tolerate duplicate output if pattern matching is used?

2

Hello @jomo6,

Welcome to the community!

This is a bit complex to digest, maybe make an example app that can be run locally that replicates the issue for some help?

Also, if you havent done so, you could post an issue on the github repo.

3

Hi @jinnyzor ,

Thanks, I wrote a really simple example app that generates this error, which helped me realise I need to pass allow_duplicate=True as an argument of the Output statement! As per documentation: Duplicate Callback Outputs | Dash for Python Documentation | Plotly.

I had incorrectly passed it as an argument of the @callback() decorator. My mistake!

1 Like
4

Great news!

Glad you figured it out. I often find that starting from scratch can help with solving issues. :slight_smile: