It ain't pretty but this should work 
my $directory =
  "${\$machine->work_dir}/subdir/${\$machine->software_version}/";

[download]
But as it stands perl sees your string as 
my $directory =
  $machine."->work_dir/subdir/".$machine."->software_version}/";

[download]
So you might need to either change the users' interface or force a style on them and definitely not use a source filter.
HTH

_________
broquaint

In reply to Re: Changing -> to work within a string by broquaint
in thread Changing -> to work within a string by shushu

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