Unusual if statement in MaterialDesign codebase - would appreciate help

[sabuncumurat]

Hi, when browsing the codebase, I came across the following if statement:

I have not kept up with changes in the C# language, would appreciate if you could explain how the braces and the variable work.

And most importantly, what is the official name of this construct in C# standard?

[Keboo]

The name for this is "property pattern matching". It is both performing a null check, but if the value of HintProxy is not null, it will assign the non-null value to hintProxy and the expression returns true.

You can read more about it here: https://essentialcsharp.com/pattern-matching#property-patterns-c-8-0-10-0

[sabuncumurat]

Thank you so much for this.
Regards.