What is the fundamental reason that Dash choose to not allow multiple callbacks for same output?

[victorx]

One of the annoying constraint of Dash is you can’t have multiple callbacks output to the same component+property. While there is a 3rd party package dash-extension which can work around it to some extent, it does not work for the callbacks using flexible signature of Dash 2.0 nor for client side callback.

I was wondering what was the fundamental reason which made the authors of the Dash to impose such constraint. IMHO, supporting multiple callbacks output to the same component+property does not seem to have any fundamental difficulty, as long as they have different input dependencies.

Any thoughts?

[jlfsjunior]

Hi,

You can find this specific discussion in this post:

Duplicate Callback Outputs - Solution & API Discussion

Hello everyone – In yesterday’s Dash 2.0 webinar, there were a surprising (to me!) number of questions asking if we “allow multiple callbacks to update the same output.” I wanted to kick off a discussion of this topic. How to do this today Here is the canonical working example that allows you to update an output. This works! It allows you to target a single input from multiple inputs. from dash import Dash, callback, Input, Output, State, callback_context, html, dcc import plotly.exp…

[Emil]

What issue do you have with clientside callbacks?

Support for flexible callback signatures is on the roadmap. I expect to add support soon.