[Issue 23647] New: Better error message on untyped function parameter

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23647

          Issue ID: 23647
           Summary: Better error message on untyped function parameter
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: grimmaple95 at gmail.com

```
void foo(int i, j)
{
    writeln(i, " ", j);
}
```

This code generates a following error:
onlineapp.d(3): Error: undefined identifier `j`

It's probably better to say something like `Expected type, not variable`

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