added statis map object and used it to implement builtins. Also, new objects File and Directory

src/objects/o_dir.c

@@ -0,0 +1,53 @@
+#include "objects.h"
+
+typedef struct {
+	Object base;
+	DIR *dir;
+} DirObject;
+
+static _Bool dir_free(Object *obj, Error *error);
+
+static TypeObject t_dir = {
+	.base = (Object) { .type = &t_type, .flags = Object_STATIC },
+	.name = "Directory",
+	.size = sizeof(DirObject),
+	.free = dir_free,
+};
+
+_Bool Object_IsDir(Object *obj)
+{
+	return obj->type == &t_dir;
+}
+
+Object *Object_FromDIR(DIR *handle, Heap *heap, Error *error)
+{
+	DirObject *dob = (DirObject*) Heap_Malloc(heap, &t_dir, error);
+
+	if(dob == NULL)
+		return NULL;
+
+	dob->dir = handle;
+
+	return (Object*) dob;
+}
+
+DIR *Object_ToDIR(Object *obj, Error *error)
+{
+	if(!Object_IsDir(obj))
+		{
+			Error_Report(error, 0, "Object is not a directory");
+			return NULL;
+		}
+
+	return ((DirObject*) obj)->dir;
+}
+
+static _Bool dir_free(Object *obj, Error *error)
+{
+	DirObject *dob = (DirObject*) obj;
+	if(closedir(dob->dir) == 0)
+		return 1;
+
+	Error_Report(error, 0, "Failed to close directory");
+	return 0;
+}