Any way to evaluate expressions in .NET C#?

[marcinjahn]

I wonder, is it possible to evalutate expressions during debugging? Let's say, I hit a breakpoint, and while my program is paused, I want to execute some expression just to see what will be the result. In IDEs like Rider or VS, I can do that, what about neovim+dap? In Dap UI, there's an Expressions panel, but it seems to only allow me to add some varaibles to Watch? When I try to execute something like var x = 1, I get:

Am I doing something wrong, or is it a missing feature?