nixir

diff --git a/src/irc/evaluator.cpp b/src/irc/evaluator.cppindex 7a50dc7..987e38a 100644--- a/src/irc/evaluator.cpp+++ b/src/irc/evaluator.cpp@@ -21,15 +21,20 @@ struct IREnvironment {    void bind(Value* val) { bindings.push_back(val); } -  Value* lookup(uint32_t index) {+  Value* lookup(uint32_t encoded_index) {+    // Decode the index: high 16 bits = depth, low 16 bits = offset+    uint32_t depth = encoded_index >> 16;+    uint32_t offset = encoded_index & 0xFFFF;+     IREnvironment* env = this;-    while (env) {-      if (index < env->bindings.size()) {-        return env->bindings[index];-      }-      index -= env->bindings.size();+    // Skip 'depth' levels to get to the right scope+    for (uint32_t i = 0; i < depth && env; i++) {       env = env->parent;     }++    if (env && offset < env->bindings.size()) {+      return env->bindings[offset];+    }     return nullptr;   } @@ -147,7 +152,35 @@ struct Evaluator::Impl {         state.error<EvalError>("variable not found").debugThrow();       }       force(bound);-      v = *bound;+      // Copy the forced value's data into v+      // For simple types, use mk* methods to ensure proper initialization+      // For complex types (attrs, lists, functions), direct assignment is safe+      state.forceValue(*bound, noPos);+      switch (bound->type()) {+      case nInt:+        v.mkInt(bound->integer());+        break;+      case nBool:+        v.mkBool(bound->boolean());+        break;+      case nString:+        v.mkString(bound->c_str());+        break;+      case nPath:+        v.mkPath(bound->path());+        break;+      case nNull:+        v.mkNull();+        break;+      case nFloat:+        v.mkFloat(bound->fpoint());+        break;+      default:+        // For attrs, lists, functions, etc., direct assignment is safe+        // as they use reference counting internally+        v = *bound;+        break;+      }     } else if (auto* n = node->get_if<LambdaNode>()) {       auto lambda_env = env;       auto body = n->body;@@ -422,20 +455,33 @@ struct Evaluator::Impl {       }     } else if (auto* n = node->get_if<LetNode>()) {       auto let_env = make_env(env);+      // Nix's let is recursive: bind all names first, then evaluate+      // We allocate Values immediately and evaluate into them+      std::vector<Value*> values;       for (const auto& [name, expr] : n->bindings) {-        // Create thunks in let_env so bindings can reference each other-        Value* val = make_thunk(expr, let_env);+        Value* val = state.allocValue();+        values.push_back(val);         let_env->bind(val);       }+      // Now evaluate each binding expression into its pre-allocated Value+      size_t idx = 0;+      for (const auto& [name, expr] : n->bindings) {+        eval_node(expr, *values[idx++], let_env);+      }       eval_node(n->body, v, let_env);     } else if (auto* n = node->get_if<LetRecNode>()) {       auto letrec_env = make_env(env);-+      // Same as LetNode - both are recursive in Nix+      std::vector<Value*> values;       for (const auto& [name, expr] : n->bindings) {-        Value* val = make_thunk(expr, letrec_env);+        Value* val = state.allocValue();+        values.push_back(val);         letrec_env->bind(val);       }-+      size_t idx = 0;+      for (const auto& [name, expr] : n->bindings) {+        eval_node(expr, *values[idx++], letrec_env);+      }       eval_node(n->body, v, letrec_env);     } else if (auto* n = node->get_if<AttrsetNode>()) {       auto bindings = state.buildBindings(n->attrs.size());@@ -453,9 +499,12 @@ struct Evaluator::Impl {         }       } -      // Attributes should be lazy, so store as thunks and not evaluated values+      // Evaluate attribute values immediately to avoid dangling thunks+      // Our thunk system is tied to the Evaluator lifetime, so we can't+      // return lazy thunks that outlive the evaluator       for (const auto& binding : n->attrs) {-        Value* attr_val = make_thunk(binding.value, attr_env);+        Value* attr_val = state.allocValue();+        eval_node(binding.value, *attr_val, attr_env);          if (binding.is_dynamic()) {           // Evaluate key expression to get attribute name@@ -498,7 +547,35 @@ struct Evaluator::Impl {       if (attr) {         Value* val = attr->value;         force(val);-        v = *val;+        // Copy the forced value's data into v+        // For simple types, use mk* methods to ensure proper initialization+        // For complex types (attrs, lists, functions), direct assignment is safe+        state.forceValue(*val, noPos);+        switch (val->type()) {+        case nInt:+          v.mkInt(val->integer());+          break;+        case nBool:+          v.mkBool(val->boolean());+          break;+        case nString:+          v.mkString(val->c_str());+          break;+        case nPath:+          v.mkPath(val->path());+          break;+        case nNull:+          v.mkNull();+          break;+        case nFloat:+          v.mkFloat(val->fpoint());+          break;+        default:+          // For attrs, lists, functions, etc., direct assignment is safe+          // as they use reference counting internally+          v = *val;+          break;+        }       } else if (n->default_expr) {         eval_node(*n->default_expr, v, env);       } else {