parser: Ensure the expression types

When assign a variable or returning a value it now ensures that the
expression matches the expected type.

To make this possible a %result_type% field was added to ast_node_t and
this field is used whenever to make the comparison.

Signed-off-by: Carlos Maniero <carlos@maniero.me>
Signed-off-by: Johnny Richard <johnny@johnnyrichard.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/src/ast.h b/src/ast.h
index 80148dc..f91632c 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -23,7 +23,8 @@
 typedef enum
 {
   TYPE_I32,
-  TYPE_BOOL
+  TYPE_BOOL,
+  TYPE_VOID,
 } type_t;
 
 typedef struct ast_node_t ast_node_t;
@@ -124,8 +125,12 @@ typedef struct ast_node_t
 {
   ast_node_kind_t kind;
   ast_node_data_t data;
+  type_t result_type;
 } ast_node_t;
 
+char *
+ast_type_to_str(type_t type);
+
 ast_node_t *
 ast_node_new(void);
 
@@ -136,7 +141,10 @@ void
 ast_node_destroy(ast_node_t *node);
 
 ast_node_t *
-ast_node_new_binary_operation(ast_binary_operation_kind_t kind, ast_node_t *left, ast_node_t *right);
+ast_node_new_binary_operation(ast_binary_operation_kind_t kind,
+                              ast_node_t *left,
+                              ast_node_t *right,
+                              type_t result_type);
 
 ast_node_t *
 ast_node_new_function_declaration(string_view_t function_name, type_t return_type, vector_t *body);
@@ -154,7 +162,7 @@ ast_node_t *
 ast_node_new_literal_bool(bool boolean);
 
 ast_node_t *
-ast_node_new_variable(ast_identifier_t *identifier);
+ast_node_new_variable(ast_identifier_t *identifier, type_t result_type);
 
 ast_node_t *
 ast_node_new_variable_assignment(ast_identifier_t *identifier, ast_node_t *expression);