Any additions for write-to-file short program

[Imperatorn]

On Friday, 19 November 2021 at 22:21:52 UTC, pascal111 wrote:
> On Thursday, 18 November 2021 at 23:09:28 UTC, H. S. Teoh wrote:
>> [...]
>
>
> When I compiled the code after adding yours, I found this error 
> message:
>
> "untitled20.d:24:8: error: no property 'copy' for type 'ByChunk'
>    24 |        .copy(outputFile.lockingBinaryWriter); // copy 
> each block into output file
>       |        ^
> "

Did you import std.algorithm?