1 files changed, 74 insertions, 0 deletions
diff --git a/type_checker.c b/type_checker.c
new file mode 100644
index 0000000..f914c34
--- /dev/null
+++ b/type_checker.c
@@ -0,0 +1,74 @@
+#include "ast.h"
+#include "scope.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+#define TYPE_PANIC(format, ...) {\
+    fprintf(\
+        stderr,\
+        "ccc: type error: " format "\n" __VA_OPT__(,)\
+        __VA_ARGS__);\
+    exit(1);\
+}
+
+static struct scope* scope;
+
+static void type_check_group(struct group_node* node);
+
+static void type_check_expr(struct expr_node* node) {}
+
+static void type_check_var_decl(struct var_decl_node* node) {}
+
+static void type_check_return(struct return_node* node) {}
+
+static void type_check_stmt(struct stmt_node* node) {
+    switch (node->type) {
+        case STMT_EMPTY:
+            break;
+        case STMT_EXPR:
+            type_check_expr(&node->inner.expr);
+            break;
+        case STMT_VAR_DECL:
+            type_check_var_decl(&node->inner.var_decl);
+            break;
+        case STMT_RETURN:
+            type_check_return(&node->inner.return_);
+            break;
+        case STMT_GROUP:
+            type_check_group(&node->inner.group);
+            break;
+    }
+}
+
+static void type_check_group(struct group_node* node) {
+    if (node->scope->next_out != scope) TYPE_PANIC("scopes are borked");
+    scope = node->scope;
+    struct stmt_node* stmt = node->head;
+    while (stmt != NULL) {
+        type_check_stmt(stmt);
+        stmt = stmt->next;
+    }
+}
+
+static void type_check_fn_decl(struct fn_decl_node* node) {
+    scope = node->scope;
+    type_check_group(&node->body);
+}
+
+static void type_check_root(struct root_node* node) {
+    switch (node->type) {
+        case ROOT_FN_DECL:
+            type_check_fn_decl(&node->inner.fn_decl);
+            break;
+    }
+}
+
+void type_check(struct ast* ast) {
+    scope = ast->root_scope;
+
+    struct root_node* node = ast->root_node;
+    while (node != NULL) {
+        type_check_root(node);
+        node = node->next;
+    }
+}