+extern VEC (char_ptr) *complete_internalvar (const char *name);
+
+/* An internalvar can be dynamically computed by supplying a vector of
+ function pointers to perform various operations. */
+
+struct internalvar_funcs
+{
+ /* Compute the value of the variable. The DATA argument passed to
+ the function is the same argument that was passed to
+ `create_internalvar_type_lazy'. */
+
+ struct value *(*make_value) (struct gdbarch *arch,
+ struct internalvar *var,
+ void *data);
+
+ /* Update the agent expression EXPR with bytecode to compute the
+ value. VALUE is the agent value we are updating. The DATA
+ argument passed to this function is the same argument that was
+ passed to `create_internalvar_type_lazy'. If this pointer is
+ NULL, then the internalvar cannot be compiled to an agent
+ expression. */
+
+ void (*compile_to_ax) (struct internalvar *var,
+ struct agent_expr *expr,
+ struct axs_value *value,
+ void *data);
+
+ /* If non-NULL, this is called to destroy DATA. The DATA argument
+ passed to this function is the same argument that was passed to
+ `create_internalvar_type_lazy'. */
+
+ void (*destroy) (void *data);
+};
+
+extern struct internalvar *create_internalvar_type_lazy (const char *name,
+ const struct internalvar_funcs *funcs,
+ void *data);
+
+/* Compile an internal variable to an agent expression. VAR is the
+ variable to compile; EXPR and VALUE are the agent expression we are
+ updating. This will return 0 if there is no known way to compile
+ VAR, and 1 if VAR was successfully compiled. It may also throw an
+ exception on error. */
+
+extern int compile_internalvar_to_ax (struct internalvar *var,
+ struct agent_expr *expr,
+ struct axs_value *value);