Fixes #4143. ReactiveExample throw System.NotSupportedException: 'Index expressions are only supported with constants.'

[BDisp]

Fixes

• Fixes ReactiveExample throw System.NotSupportedException: 'Index expressions are only supported with constants.' #4143

Proposed Changes/Todos

• Replace BindTo with Subscribe method

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[tig]

Thanks for figuring this out!

I had noticed this when I did the Scheme work, tried to figure it out, gave up with a plan to fix it eventually, and then forgot about it ;-).

You rock!