Is it possible to assign a Comma Expression to a variable?

[Lucian Danescu]

To give some context, D-Scanner has a check that warns against 
assigning a comma expression to a variable. Example:

```
a = (foo(), bar(), 1); // warn here
```

This check was implemented a while back, and from what I can see, 
currently assigning a comma expression results in a compilation 
error, hence that check in D-Scanner would not be necessary 
anymore.

I just wanted to make sure that it is impossible to assign a 
comma expression to a variable, or if it is possible, can someone 
please clarify when and maybe give an example?