Refactor parser to use Token in AST and update tests

v0/ast.h

@@ -5,29 +5,79 @@
 #define AST_H
 
 #include "bool.h"
+#include "token.h"
+
 #include <stddef.h>
 
 typedef struct {
-    /* @brief The name of the module being imported. */
-    char* module_name;
+    /** @brief The name of the module being imported. */
+    Token module_name;
 
-    /* @brief Whether the import is public or not. */
+    /** @brief Whether the import is public or not. */
     bool is_public;
 } ImportDeclaration;
 
+typedef enum {
+    TYPE_EXPRESSION_BUILTIN,
+    TYPE_EXPRESSION_ARRAY
+} TypeExpressionTag;
+
+/**
+ * An expression that evaluates to a type.
+ */
+typedef struct TypeExpression TypeExpression;
+struct TypeExpression{
+    /** @brief defines which entry in the union is valid */
+    TypeExpressionTag tag;
+    union {
+        /** @brief Evaluates to an array of the given type. */
+        struct {
+            /** @brief A pointer to the type of the elements stored in the array. */
+            TypeExpression* array;
+        } array;
+        /** @brief Evaluates to a builtin integer type.*/
+        struct {
+            /**
+             * @brief The number of bits in the integer.
+             * Typical values are 8, 16, 32, and 64.
+             */
+            int bitSize;
+            /** @brief `true` if the type is signed, `false` if it's unsigned. */
+            bool isSigned;
+        } builtin;
+    };
+};
+
+/**
+ * A declaration that aliases one type to another.
+ */
+typedef struct {
+    /** @brief The name of the alias. */
+    Token name;
+
+    /** @brief The value of the alias. */
+    TypeExpression value;
+} AliasDeclaration;
+
 /**
  * The top-level model.
  * Every file matches an entire Module.
  */
 typedef struct {
-    /* @brief The name of the module. */
-    char* name;
+    /** @brief The name of the module. */
+    Token name;
 
-    /* @brief The list of imports in the module. */
+    /** @brief The list of imports in the module. */
     ImportDeclaration* imports;
 
-    /* @brief The number of imports in the module. */
+    /** @brief The number of imports in the module. */
     size_t import_count;
+
+    /** @brief The list of aliases in the module. */
+    AliasDeclaration* aliases;
+
+    /** @brief The number of aliases in the module. */
+    size_t alias_count;
 } Module;
 
 #endif