void psi_let_callback_free(struct psi_let_callback **cb_ptr);
void psi_let_callback_dump(int fd, struct psi_let_callback *cb, unsigned level);
bool psi_let_callback_validate(struct psi_data *data, struct psi_let_exp *exp, struct psi_let_callback *cb, struct psi_impl *impl);
void psi_let_callback_free(struct psi_let_callback **cb_ptr);
void psi_let_callback_dump(int fd, struct psi_let_callback *cb, unsigned level);
bool psi_let_callback_validate(struct psi_data *data, struct psi_let_exp *exp, struct psi_let_callback *cb, struct psi_impl *impl);