retrieve url parameters into variable

As a follow-up to Py-Shiny Url Parameters, is it possible to 'merely call' the reactive function and retrieve the value, (without reactivity) and use the value in a computation/function?

It seems that if the 'out()' function is declared as an 'reactive.effect' it is never called.

Also, can that reactive value be used as the initial value in an input_text as in:

    ui.input_text('ui_value', 'Value', out() ),

Thank you.