$query =~ s/([^ !#\$%()*,\/:;<=>?\@[\]^{|}~]+)/mash_l($1)/eg ;

  sub mash_l {
    my ($s) = @_ ;

    return $s if $s =~ /^(?:[a-z]+|\+|\-)$/ ;

    return 'N' if $s =~ /^[+-]?(?:
                                 (?:\d+(?:\.\d*)? | \.\d+) (?:e[+-]\d+)?
                                |(?:0(?:
                                        x[0-9a-f]+
                                       |b[01]+
                                      )
                                 )
                                |x'[0-9a-f]+'
                                |b'[01]+'
                               )$/x ;

    return 'S' if $s =~ /^(["']).*?\1$/ ;

    return $s ;
  } ;