Phobos function to check if files are identical?

[XavierAP via Digitalmars-d-learn]

On Tuesday, 14 March 2017 at 18:26:52 UTC, flamencofantasy wrote:
>
>   import std.mmfile;
>
>   auto f1 = new MmFile("file1");
>   auto f2 = new MmFile("file2");
>
>   return f1[] == f2[];

Nice! I don't have experience with memory-mapped files. What are 
the pros and cons?