Allow empty value in gr.Number

[hannahblair]

Description

We should allow empty values to be shown on the frontend in gr.Number when its None/null. I've not changed the data type of value itself but rather created a new variable which is used for displaying the value as a empty string when the value is null, and it updates whenever value updates.

Demo:

import gradio as gr

with gr.Blocks() as demo:
    gr.Number(value=None)

demo.launch()

Closes: #6728

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/4671c89b14fb3012a13b92802019e60a368e2960/gradio-4.40.0-py3-none-any.whl

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🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/number	patch
gradio	patch

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Allow empty value in gr.Number

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[hannahblair]

Tests failing, will change implementation

[abidlabs]

IIUC this change should have no effect since the first branch terminates in a return statement, am I misunderstanding?

[abidlabs]

This means that browsers won't treat this field as numeric. On Desktop it means we'll lose these:

On mobile, I think it will lead to a ux degradation since the numeric keyboard won't pop up anymore

[abidlabs]

I don't think this change should be needed since at least according to the original issue, it is in theory possible to set a numeric field blank:

Currently, I can set the value to Callable, where Callable returns None. I have tested this, and the frontend displays it as blank, which aligns with my requirements.

[hannahblair]

This means that browsers won't treat this field as numeric. On Desktop it means we'll lose these:

Thats a good point, we don't want to lose that :/

[hannahblair]

In light of your comment I'll close the issue in which case. Thanks for reviewing nonetheless!