work on generic extend

src/built_ins.cpp

@@ -366,6 +366,18 @@ proc load_built_ins_into_environment() -> void {
 
         return Memory::create_lisp_object_number(x);
     };
+    define_special((bound? var), "TODO") {
+        fetch(var);
+        try assert_type(var, Lisp_Object_Type::Symbol);
+
+        Lisp_Object* res;
+        in_caller_env {
+            res = try_lookup_symbol(var, get_current_environment());
+        }
+        if (res)
+            return Memory::t;
+        return Memory::nil;
+    };
     define((assert test), "TODO") {
         fetch(test);
 
@@ -541,12 +553,18 @@ proc load_built_ins_into_environment() -> void {
         in_caller_env {
             val = eval_expr(val);
             target_env = find_binding_environment(sym, get_current_environment());
-            try assert(target_env);
+            if (!target_env)
+                target_env = get_root_environment();
         }
 
 
         push_environment(target_env);
         {
+            printf("set!ing:: ");
+            print(sym);
+            printf(" to ");
+            print(val);
+            printf(" in %llu\n", (unsigned long long) target_env);
             define_symbol(sym, val);
         }
         pop_environment();

src/env.cpp

@@ -14,11 +14,11 @@ proc environment_binds_symbol(Lisp_Object* sym, Environment* env) -> bool {
 proc find_binding_environment(Lisp_Object* sym, Environment* env) -> Environment* {
     if (environment_binds_symbol(sym, env))
         return env;
-    for (int i = 0; i < env->parents.next_index; ++i) {
-        if (environment_binds_symbol(sym, env->parents.data[i]))
-            return env->parents.data[i];
+    for_array_list (env->parents) {
+        if (Environment* ret = find_binding_environment(sym, it))
+            return it;
     }
-    return get_root_environment();
+    return nullptr;
 }
 
 proc try_lookup_symbol(Lisp_Object* node, Environment* env) -> Lisp_Object* {
@@ -34,7 +34,7 @@ proc try_lookup_symbol(Lisp_Object* node, Environment* env) -> Lisp_Object* {
         if (result)
             return result;
     }
-    
+
     auto nil_sym = Memory::get_or_create_lisp_object_symbol("nil");
     auto t_sym   = Memory::get_or_create_lisp_object_symbol("t");