commit cbe9c07

Add natives

  1@@ -15,13 +15,14 @@ typedef struct environment environment;
  2 typedef struct parser parser;
  3 
  4 struct function {
  5-	expl_node* args;
  6-	expl_node* body;
  7+	expl_native native;
  8+	expl_node*  args;
  9+	expl_node*  body;
 10 };
 11 
 12 struct environment {
 13 	char*        name;
 14-	expl_node*   value;
 15+	expl_value   value;
 16 	environment* next;
 17 };
 18 
 19@@ -31,14 +32,15 @@ struct parser {
 20 	expl_error  err;
 21 };
 22 
 23-static int define(environment** env, const char* name, expl_node* value);
 24+static int define(environment** env, const char* name, expl_value value);
 25 static expl_node* expression(parser* p);
 26 static expl_node* list(parser* p);
 27-static expl_node* lookup(environment* env, const char* name);
 28+static expl_value* lookup(environment* env, const char* name);
 29 static expl_node* value(parser* p, expl_type type);
 30 
 31-static expl_node* eval(expl_node* n, environment** env);
 32-static expl_node* eval_let(expl_node* args, environment** env);
 33+static expl_value eval(expl_node* n, environment** env);
 34+static expl_value eval_call(expl_node* args, environment** env);
 35+static int register_native(environment** env, const char* name, expl_native fn);
 36 
 37 static void skip_space(parser* p);
 38 static char* _strndup(const char* src, size_t len);
 39@@ -49,7 +51,7 @@ static void free_node(expl_node* node);
 40 static void free_environment(environment* env);
 41 
 42 static int
 43-define(environment** env, const char* name, expl_node* value)
 44+define(environment** env, const char* name, expl_value value)
 45 {
 46 	environment* b = malloc(sizeof(*b));
 47 	if (!b)
 48@@ -124,12 +126,12 @@ list(parser* p)
 49 	return node;
 50 }
 51 
 52-static expl_node*
 53+static expl_value*
 54 lookup(environment* env, const char* name)
 55 {
 56 	while (env) {
 57 		if (strcmp(env->name, name) == 0)
 58-			return env->value;
 59+			return &env->value;
 60 		env = env->next;
 61 	}
 62 
 63@@ -192,8 +194,8 @@ value(parser* p, expl_type type)
 64 	return node;
 65 }
 66 
 67-static expl_node*
 68-evaluate(expl_node* n, environment** env)
 69+static expl_value
 70+eval(expl_node* n, environment** env)
 71 {
 72 	char* end = NULL;
 73 
 74@@ -223,6 +225,28 @@ evaluate(expl_node* n, environment** env)
 75 static expl_node*
 76 eval_let(expl_node* args, environment** env)
 77 {
 78+static int
 79+register_native(environment** env, const char* name, expl_native fn)
 80+{
 81+	function* f = malloc(sizeof(*f));
 82+	expl_value value = { 0 };
 83+
 84+	if (!f)
 85+		return 0;
 86+
 87+	f->native = fn;
 88+	f->args = NULL;
 89+	f->body = NULL;
 90+
 91+	value.type = EXPL_VALUE_FUNCTION;
 92+	value.as.function = f;
 93+
 94+	if (!define(env, name, value)) {
 95+		free(f);
 96+		return 0;
 97+	}
 98+
 99+	return 1;
100 }
101 
102 static void

 1@@ -3,7 +3,7 @@
 2 
 3 #ifndef EXPL_SPACES
 4 #define EXPL_SPACES "  "
 5-#endif
 6+#endif /* EXPL_SPACES */
 7 
 8 typedef enum {
 9 	EXPL_TYPE_ATOM,
10@@ -36,6 +36,8 @@ typedef enum {
11 typedef struct expl_node expl_node;
12 typedef struct expl_value expl_value;
13 
14+typedef expl_value (*expl_native)(int argc, const expl_value* argv);
15+
16 struct expl_node {
17 	char*      value;
18 	expl_type  type;