Splitting up large dirty file

[Dennis]

On Thursday, 17 May 2018 at 21:10:35 UTC, Dennis wrote:
> It's unfortunate that Phobos tells you 'there's problems with 
> the encoding' without providing any means to fix it or even 
> diagnose it.

I have to take that back since I found out about std.encoding 
which has functions like `sanitize`, but also `transcode`. (My 
file turned out to actually be encoded with ANSI / Windows-1252, 
not UTF-8)
Documentation is scarce however, and it requires strings instead 
of forward ranges.

@Jon Degenhardt
> Instead of:
> 
>      auto outputFile = new File("output.txt");
> 
> try:
> 
>     auto outputFile = File("output.txt", "w");

Wow I really butchered that code. So it is the `drop(4)` that 
triggers the UTFException? I find Exceptions in range code hard 
to interpret.

@Kagamin
> Do it old school?

I want to be convinved that Range programming works like a charm, 
but the procedural approaches remain more flexible (and faster 
too) it seems. Thanks for the example.