widget.empty() clears the widget only at the end of the script

[Wirg]

Hi and thank you for streamlit :)

Summary

Using widget.empty() on a widget, empty the widget but only when streamlit reach the end of the script.

Steps to reproduce

from time import sleep

import streamlit as st

widget = st.empty()
widget.write("original text")

sleep(2)

widget.empty()
st.write("cleared original text")

sleep(2)

st.text("end")

Expected behavior:

I expect widget.empty() to empty the widget "instantly" when I call the function. write, progress and other widgets already work this way (here before st.write("cleared original text")).

Actual behavior:

The widget is emptied when streamlit reaches the end of the script (here, after st.text("end")).

Is this a regression?

I don't know.

Debug info

• Streamlit version: Streamlit, version 0.71.0
• Python version: Python 3.6.9
• Using Conda? PipEnv? PyEnv? Pex? : virtualenv
• OS version:

Distributor ID: Ubuntu
Description:    Ubuntu 18.04.2 LTS
Release:        18.04
Codename:       bionic

• Browser version: Version 86.0.4240.198 (Official Build) (64-bit

[akrolsmir]

Streamlit snippets of the code example: https://share.streamlit.io/akrolsmir/streamlit-snippet/main?snippet_id=FcAXRYMC

[Wirg]

Hi !

Sorry for the bump. Could you tell me if it's considered as a bug and worth fixing ?
Or is it the normal behavior and I should consider a workaround ?

Thanks

[Wirg]

Hi & Happy new year ! :)

Another bump to understand if it's considered as a bug and worth fixing ?
Or is it the normal behavior and I should consider a workaround ?

Thanks

[vdonato]

Hi! Sorry for the delay in getting back to you @Wirg, but yes this is certainly something that we're looking into fixing.

I'm actually just starting to see if I can polish the behavior of st.empty() so it works as expected.

[svats2k]

Any update on this thread?