|| (scm_is_eq (prop, ly_symbol2scm ("pitch-alist")) && scm_is_pair (val)))
&& scm_is_false (scm_assq (prop, mutable_property_alist_)))
mutable_property_alist_
|| (scm_is_eq (prop, ly_symbol2scm ("pitch-alist")) && scm_is_pair (val)))
&& scm_is_false (scm_assq (prop, mutable_property_alist_)))
mutable_property_alist_