Selector interpolation works robustly (sans a few special cases).

document.cpp

@@ -60,17 +60,18 @@ namespace Sass {
     return doc;
   }
 
-  Document Document::make_from_source_chars(Context& ctx, char* src, string path)
+  Document Document::make_from_source_chars(Context& ctx, char* src, string path, bool own_source)
   {
     Document doc(ctx);
     doc.path = path;
     doc.line = 1;
     doc.root = ctx.new_Node(Node::root, path, 1, 0);
     doc.lexed = Token::make();
-    doc.own_source = false;
+    doc.own_source = own_source;
     doc.source = src;
     doc.end = src + std::strlen(src);
-    doc.position = doc.end;
+    doc.position = src;
+    if (own_source) doc.context.source_refs.push_back(src);
 
     return doc;
   }

document.hpp

 #include <map>
 
+#ifndef SASS_PRELEXER_INCLUDED
+#include "prelexer.hpp"
+#endif
+
 #ifndef SASS_NODE_INCLUDED
 #include "node.hpp"
 #endif
 
-#include "prelexer.hpp"
+#ifndef SASS_CONTEXT_INCLUDED
 #include "context.hpp"
+#endif
 
 struct Selector_Lookahead {
   const char* found;
@@ -41,7 +46,7 @@ namespace Sass {
     ~Document();
 
     static Document make_from_file(Context& ctx, string path);
-    static Document make_from_source_chars(Context& ctx, char* src, string path = "");
+    static Document make_from_source_chars(Context& ctx, char* src, string path = "", bool own_source = false);
     static Document make_from_token(Context& ctx, Token t, string path = "", size_t line_number = 1);
 
     template <prelexer mx>

document_parser.cpp

@@ -898,6 +898,10 @@ namespace Sass {
                                    prefix_match,
                                    suffix_match,
                                    substring_match> >(p))          ||
+           (q = peek< sequence< exactly<'.'>, interpolant > >(p))  ||
+           (q = peek< sequence< exactly<'#'>, interpolant > >(p))  ||
+           (q = peek< sequence< exactly<'-'>, interpolant > >(p))  ||
+           (q = peek< sequence< pseudo_prefix, interpolant > >(p)) ||
            (q = peek< interpolant >(p))) {
       p = q;
       if (*(p - 1) == '}') saw_interpolant = true;

eval_apply.hpp

@@ -11,10 +11,10 @@
 namespace Sass {
   using std::map;
   
-  Node eval(Node& expr, Environment& env, map<pair<string, size_t>, Function>& f_env, Node_Factory& new_Node);
+  Node eval(Node& expr, Environment& env, map<pair<string, size_t>, Function>& f_env, Node_Factory& new_Node, Context& src_refs);
   Node accumulate(Node::Type op, Node& acc, Node& rhs, Node_Factory& new_Node);
   double operate(Node::Type op, double lhs, double rhs);
   
-  Node apply_mixin(Node& mixin, const Node& args, Environment& env, map<pair<string, size_t>, Function>& f_env, Node_Factory& new_Node);
-  Node apply_function(const Function& f, const Node& args, Environment& env, map<pair<string, size_t>, Function>& f_env, Node_Factory& new_Node);
+  Node apply_mixin(Node& mixin, const Node& args, Environment& env, map<pair<string, size_t>, Function>& f_env, Node_Factory& new_Node, Context& src_refs);
+  Node apply_function(const Function& f, const Node& args, Environment& env, map<pair<string, size_t>, Function>& f_env, Node_Factory& new_Node, Context& src_refs);
 }
\ No newline at end of file

sass_interface.cpp

@@ -39,21 +39,8 @@ extern "C" {
   {
     using namespace Sass;
     doc.parse_scss();
-    // cerr << "PARSED" << endl;
-    eval(doc.root, doc.context.global_env, doc.context.function_env, doc.context.new_Node);
-    // cerr << "EVALUATED" << endl;
+    eval(doc.root, doc.context.global_env, doc.context.function_env, doc.context.new_Node, doc.context);
     string output(doc.emit_css(static_cast<Document::CSS_Style>(style)));
-    // cerr << "EMITTED" << endl;
-    
-    // cerr << "Allocations:\t" << Node::allocations << endl;
-    // cerr << "Destructions:\t" << Node::destructed << endl;
-    // cerr << "Registry size:\t" << doc.context.registry.size() << endl;
-    
-    // for (size_t i = 0; i < doc.context.registry.size(); ++i) {
-    //   delete doc.context.registry[i];
-    // }
-    // cerr << "Deallocations:\t" << i << endl;
-    
     char* c_output = (char*) malloc(output.size() + 1);
     strcpy(c_output, output.c_str());
     return c_output;