import std::option; import base::*; import syntax::ast; fn expand_syntax_ext(cx: &ext_ctxt, sp: codemap::span, arg: @ast::expr, body: option::t[str]) -> @ast::expr { cx.print_backtrace(); std::io::stdout().write_line(print::pprust::expr_to_str(arg)); //trivial expression ret @{id: cx.next_id(), node: ast::expr_rec(~[], option::none), span: sp}; }