Strange implicit conversion integers on concatenation

[lngns]

It adds the equivalent char value, which is interpreted as ASCII 
when printing.
You can append an object of its underlying (or a compatible) type 
to an array.

```
void main()
{
     import std.stdio : writeln;

     writeln("hello " ~ 42); //hello *
     writeln([42, 56] ~ 7); //[42, 56, 7]
}
```