1 files changed, 98 insertions, 0 deletions
diff --git a/src/builtin.h b/src/builtin.h
new file mode 100644
index 0000000..144ed4c
--- /dev/null
+++ b/src/builtin.h
@@ -0,0 +1,98 @@
+#include "value.h"
+
+#define PROCEDURES(X)             \
+/*  X(symbol, name, argc) */      \
+    X(plus,   "+",  2)            \
+    X(minus,  "-",  2)            \
+    X(cons,   "cons", 2)          \
+    X(car,    "car", 1)           \
+    X(cdr,    "cdr", 1)           \
+
+// Number of builtin procedures
+#define PLUS_ONE(_symbol, _name, _argc) 1 +
+#define BUILTIN_PROCEDURES PROCEDURES(PLUS_ONE) 0
+
+// Forward decalration of the procedures
+#define DECLARE_PROCEDURE(proc) value_t proc(value_t *args)
+#define FORWARD_DECLARATION(symbol, _name, _argc) \
+    DECLARE_PROCEDURE(symbol);
+
+PROCEDURES(FORWARD_DECLARATION)
+
+// Fill procedure struct for the value_t
+#define PROC_DESCRIPTION(symbol, _name, argc) \
+    {argc, symbol},
+
+struct proc_builtin builtin_proc_descriptions[] = {
+    PROCEDURES(PROC_DESCRIPTION)
+};
+
+// List of ordered names of procedures
+#define PROC_NAME(symbol, name, _argc) \
+    name,
+
+const char *builtin_proc_name_list[] = {
+    PROCEDURES(PROC_NAME)
+};
+
+// ----- Definitions -----
+
+#define ASSERT_TYPE(proc, args, pos, vtype, fail)           \
+    if(args[pos]->type != vtype) {                          \
+        err("Expected arg %d of %s to be %s instead of %s", \
+            pos, #proc, "", "");                            \
+        fail;                                               \
+    }
+
+#define PROC_ASSERT_TYPE(pos, vtype, fail)                  \
+    ASSERT_TYPE(P, args, pos, vtype, fail)
+
+#define P plus
+DECLARE_PROCEDURE(P)
+{
+    PROC_ASSERT_TYPE(0, VALUE_INT, return VALUE_EMPTY);
+    PROC_ASSERT_TYPE(1, VALUE_INT, return VALUE_EMPTY);
+
+    int sum = args[0]->value.num + args[1]->value.num;
+    return value_create(VALUE_INT, &sum);
+}
+#undef P
+
+#define P minus
+DECLARE_PROCEDURE(P)
+{
+    PROC_ASSERT_TYPE(0, VALUE_INT, return VALUE_EMPTY);
+    PROC_ASSERT_TYPE(1, VALUE_INT, return VALUE_EMPTY);
+
+    int difference = args[0]->value.num - args[1]->value.num;
+    return value_create(VALUE_INT, &difference);
+}
+#undef P
+
+#define P cons
+DECLARE_PROCEDURE(P)
+{
+    struct cons cons = {value_copy(args[0]), value_copy(args[1])};
+    return value_create(VALUE_CONS, &cons);
+}
+#undef P
+
+#define P car
+DECLARE_PROCEDURE(P)
+{
+    PROC_ASSERT_TYPE(0, VALUE_CONS, return VALUE_EMPTY);
+
+    value_t left = value_copy(args[0]->value.cons.left);
+    return left;
+}
+#undef P
+
+#define P cdr
+DECLARE_PROCEDURE(P)
+{
+    PROC_ASSERT_TYPE(0, VALUE_CONS, return VALUE_EMPTY);
+
+    value_t right = value_copy(args[0]->value.cons.right);
+    return right;
+}
+#undef P