Use ruby as a preprocessor.
Usage: rbsubst [options] [file1 file2 ...]
Process the standard input or given text files treating lines starting by PREFIX
as ruby script. Non ruby lines are treated using ruby string substitutions.
Options:
-d, --[no-]debug Print the generated script on standard error
--prefix PREFIX Prefix to be used (default #!RB!#)
--marker MARKER Marker to delimit strings (default EOF_RB)
-h, --help Show this message