wip: inject scope with dependent sigma binders

Author: leissa

thorin/fe/ast.cpp

@@ -59,8 +59,11 @@ const Def* SigmaBndr::type(World& world) const {
  */
 
 void SigmaBndr::inject(Scopes& scopes, const Def* def) const {
-    size_t n = num_bndrs();
-    for (size_t i = 0; i != n; ++i) scopes.bind(bndr(i)->sym(), def->proj(n, i));
+    for (size_t i = 0, e = num_bndrs(); i != e; ++i) {
+        auto elem = def->proj(e, i);
+        scopes.bind(bndr(i)->sym(), elem);
+        bndr(i)->inject(scopes, elem);
+    }
 }
 
 } // namespace thorin::fe

thorin/fe/parser.cpp

@@ -517,6 +517,8 @@ std::unique_ptr<SigmaBndr> Parser::parse_sigma_bndr(Tracker track, Sym sym) {
 
     scopes_.push();
     parse_list("sigma binder", Tok::Tag::D_bracket_l, [&]() {
+        if (!bndrs.empty()) bndrs.back()->inject(scopes_, infers.back());
+
         bndrs.emplace_back(parse_bndr("element of a sigma binder"));
         const auto& bndr = bndrs.back();
         auto type        = bndr->type(world());