Using file as input to stdin when compiling

[Jamie]

On Tuesday, 6 February 2018 at 06:10:30 UTC, Jamie wrote:
> Hi, I'm following through TDPL and am trying to import a txt 
> file during compiling for the stdin.byLine() function to read. 
> Currently I have
>
> #!/usr/bin/rdmd <file.txt
> .
> .
> .
> foreach (line; stdin.byLine()) {
>
> }
>
> and would like it to analyse the supplied text file. Is this 
> possible in the way that I'm thinking, or is there another way?
>
> Thanks

I've figured out how to do it if I don't use the 1st line above, 
and manually compile and then execute:

$ rdmd code.d < file.txt

but still can't do it through the code file.