apart from forgetting a fi, your using the wrong braces: (something) calls "something" in a subshell, which always returns true. The syntax you're looking for is:

if  test $? -eq 0
then
else
fi
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or alternatively

if [  $? -eq 0 ]
then
else
fi
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Use square braces in stead of round ones. finally, it might be easier to use:

cd go_to_dir_where_perl_program_exists  &&
if   /usr/bin/perl perlscript.pl
   then echo "success"
   # do some more stuff
else
  echo "failure"
  # do some more stuff
fi
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