G'day Richard,

Passing embedded code in filenames is probably not the best course of action. I suspect what you really want is something more like: 

$ perl -E '
    my ($d, $m, $y) = (localtime)[3..5];
    say  $ARGV[0], "_", $d, $m+1, $y+1900, ".log";
' filename
filename_17122019.log

[download]

However, to answer your specific question, you'd probably want string eval. Do read that documentation closely for all sorts of things to be aware of. It's generally best to avoid string eval unless you have no other recourse. Here's an example of how it might work in your scenario. 

$ perl -E '
    my $x = $ARGV[0];
    my ($start, $middle, $end) = $x =~ /^([^`]+)(.+?)([^`]+)$/;
    chomp(my $mid_eval = eval $middle);
    say $start, $mid_eval, $end;
' 'filename_`date +%d%m%Y`.log'
filename_17122019.log

[download]

Note that I didn't need two levels of quotes.

— Ken

In reply to Re: backticks execution "inside" variable (string) by kcott
in thread backticks execution "inside" variable (string) by richard.sharpe

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