I'm new to Spirit and trying to put a parser together for a very simple
language of S expressions. [Note: while I'm new to Spirit, I'm not new
to parsers or parser combinators.]

This is sort of an obnoxious email because it's basically "here, solve
my problem for me even though I haven't read the docs as well as I
could", but I figured I'd ask anyway; so if you take a look, I'm much
appreciative.

I define some tokens
   template <typename Lexer>
   struct tokens : lex::lexer<Lexer> {
     tokens()  {
         this->self.add
             ("(",         Tokens::L_Paren)
             (")",         Tokens::R_Paren)
             ("\"...\"",   Tokens::String_Literal)
            ("[0-9]+",    Tokens::Integer_Literal)
             ("[a-zA-Z]+", Tokens::Symbol)
             ;
       }
   };

Then a grammar:
   template <typename Iterator>
   struct sexp_grammar
     : qi::grammar<Iterator, SExp::Ptr(), space_type>
   {
     qi::rule<Iterator, SExp::Ptr(), space_type> sexp;
     qi::rule<Iterator, vector<SExp::Ptr>(), space_type> sexp_list;

     sexp_grammar()
        : sexp_grammar::base_type(sexp)
     {
        using qi::token;
        using namespace Tokens;

        sexp_list = *sexp;

        sexp = token(String_Literal)
            |  token(Integer_Literal)
            |  token(Symbol)
            | (token(L_Paren)
               >> sexp_list
               >> token(R_Paren)
               );
     }
   };

(SExp is a class, and SExp::Ptr is a typedef to shared_ptr<SExp>.)

If I change the  also tried removing the template parameters other than
Iterator in the rules, and that let it compile (albeit with a warning).

I get oodles of errors (compiling with GCC 4.6 with
    g++ -o src/parser.os -c -std=c++0x -g -Wall -Wextra
        -Wnon-virtual-dtor -fPIC -Iinclude src/parser.cc)
which I'm not even going to try to paste into this email and you can
look at pastebin instead:
    http://pastebin.com/R5Hk9gJ0

The full code can be seen at
   https://github.com/EvanED/simple_sexp/blob/master/src/parser.cc