Add initial boilerplate for closure capture

1 files changed, 31 insertions, 1 deletions

diff --git a/src/parser.c b/src/parser.c
index 0968ccd..e72675f 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -474,6 +474,14 @@ insert_params(Environment *env, Object *symbol) {
 }
 
 void
+insert_captured(Environment *env, Object *symbol) {
+    if (find_var_index(env->captured, symbol) != -1) {
+        return;
+    }
+    array_push(env->captured, symbol);
+}
+
+void
 semantic_analysis(Environment *env, Object *obj, Errors *errors) {
     if (obj == NULL || obj->visited) {
         return;
@@ -481,7 +489,27 @@ semantic_analysis(Environment *env, Object *obj, Errors *errors) {
     obj->visited = true;
     switch (obj->type) {
         case OBJ_TYPE_SYMBOL: {
-            Object *found = symbol_in_env(env, obj);
+            Object *found = NULL;
+
+            Environment *cur_env = env;
+            while (cur_env != NULL) {
+                ssize_t idx = find_var_index(cur_env->locals, obj);
+                if (idx != -1) {
+                    found = cur_env->local_values[idx];
+                    if (cur_env != env && cur_env->parent != NULL) {
+                        insert_captured(env, obj);
+                    }
+                    break;
+                }
+                idx = find_var_index(cur_env->params, obj);
+                if (idx != -1) {
+                    found = cur_env->params[idx];
+                    break;
+                }
+                cur_env = cur_env->parent;
+            }
+
+            // Check if symbol is in other environments.
             if (found == NULL) {
                 error_push(errors, (Error){
                     .type = ERR_TYPE_PARSER,
@@ -645,6 +673,7 @@ env_alloc(Environment *parent) {
     array_init(env->locals, 0);
     array_init(env->local_values, 0);
     array_init(env->params, 0);
+    array_init(env->captured, 0);
     env->parent = parent;
     array_push(environments, env);
     return env;
@@ -687,6 +716,7 @@ free_objects(void) {
             array_free(env->locals);
             array_free(env->local_values);
             array_free(env->params);
+            array_free(env->captured);
             free(env);
         }
         array_free(environments);