Null conditional assignment operator

[UnoSD]

Please consider this enhancement:

Any version:

Null conditional assignment:

Would be nice to have an operator to assign a value just when it's null:

    // If values is null, execute statement on the right and assign.
    values ?= new List<string>();

    // Instead of:
    if(values == null) values = new List<string>();

    // Or even worse:
    values = values ?? (values = new List<string>());

[bbarry]

#205