assumeNoGC works but can't get an assumePure to work

[Paul Backus]

On Monday, 3 September 2018 at 22:07:10 UTC, aliak wrote:
> Why does it work with nogc but not with pure?
>
> Cheers,
> - Ali

You can't define an impure function inside a pure unittest. If 
you move `modify` outside the unittest block, and change the 
argument from a lambda to a function pointer, it works:

https://run.dlang.io/is/xRS75H