From 6a035a71ebe031b2f3727b805ac1aa505d880473 Mon Sep 17 00:00:00 2001
From: samsonium <me@samsonium.ru>
Date: Mon, 2 Nov 2026 19:24:09 +0300
Subject: [PATCH] wip: working on extern

- Ref: move extern header into common scope
- Feat: add extern symbols descriptors
- Feat: add `is_out` flag in declaration node
---
 include/common/fzl_extern.h         | 72 +++++++++++++++++++++++++++++
 include/compiler/fzl_parser.h       |  2 +
 include/compiler/utils/fzl_extern.h | 16 -------
 3 files changed, 74 insertions(+), 16 deletions(-)
 create mode 100644 include/common/fzl_extern.h
 delete mode 100644 include/compiler/utils/fzl_extern.h

diff --git a/include/common/fzl_extern.h b/include/common/fzl_extern.h
new file mode 100644
index 0000000..59971f6
--- /dev/null
+++ b/include/common/fzl_extern.h
@@ -0,0 +1,72 @@
+#ifndef FZL_EXTERN_H
+#define FZL_EXTERN_H
+
+#include <common/fzl_types.h>
+#include <stddef.h>
+
+// External library entry types
+typedef enum
+{
+  FZL_EXTERN_KIND_PRIMITIVE,
+  FZL_EXTERN_KIND_HANDLE,
+  FZL_EXTERN_KIND_STRUCT,
+  FZL_EXTERN_KIND_REF,
+  FZL_EXTERN_KIND_ALIAS,
+} fzl_extern_kind_t;
+
+// External library structure field descriptor
+typedef struct
+{
+  char *name;
+  fzl_type_t type;
+} fzl_extern_struct_field_t;
+
+// Extern symbol type descriptor
+typedef struct fzl_extern_type
+{
+  size_t lib_slot;
+  fzl_extern_kind_t kind;
+  char *symbol_name;
+  char *used_name;
+
+  union
+  {
+    // Structure data
+    struct
+    {
+      fzl_extern_struct_field_t **fields;
+      size_t fields_count;
+    } structure;
+
+    // Reference
+    struct fzl_extern_type *ref_of;
+
+    // Aliasing type
+    fzl_type_t alias;
+
+    // Primitive type
+    // NOTE: same type as `.alias` just for readable format
+    fzl_type_t primitive;
+  };
+} fzl_extern_type_t;
+
+// Extern symbol function descriptor
+typedef struct
+{
+  size_t lib_slot;
+  char *symbol_name;
+  char *used_name;
+
+  fzl_extern_type_t *ret_type;
+
+  fzl_extern_type_t **args;
+  size_t args_count;
+} fzl_extern_fn_t;
+
+// External library descriptor
+typedef struct
+{
+  char *name;
+} fzl_extern_lib_t;
+
+#endif // FZL_EXTERN_H
diff --git a/include/compiler/fzl_parser.h b/include/compiler/fzl_parser.h
index c91dde9..2b40a78 100644
--- a/include/compiler/fzl_parser.h
+++ b/include/compiler/fzl_parser.h
@@ -3,6 +3,7 @@
 
 #include <compiler/fzl_reader.h>
 #include <compiler/fzl_token.h>
+#include <stdbool.h>
 #include <stddef.h>
 
 // AST node type
@@ -106,6 +107,7 @@ typedef struct fzl_node
     {
       fzl_token_t *type;
       struct fzl_node *identifier;
+      bool is_out;
     } var;
 
     // Conditional blocks
diff --git a/include/compiler/utils/fzl_extern.h b/include/compiler/utils/fzl_extern.h
deleted file mode 100644
index 2fe0815..0000000
--- a/include/compiler/utils/fzl_extern.h
+++ /dev/null
@@ -1,16 +0,0 @@
-#ifndef FZL_EXTERN_H
-#define FZL_EXTERN_H
-
-// Library symbol descriptor
-typedef struct
-{
-  //
-} fzl_extern_item_t;
-
-// External library descriptor
-typedef struct
-{
-  //
-} fzl_extern_lib_t;
-
-#endif // FZL_EXTERN_H