once. If you are using C<Perl_custom_op_xop> to retreive a
C<XOP *> from a C<OP *>, use the more efficient L</XopENTRYCUSTOM> instead.
=for apidoc Am||XopENTRYCUSTOM|const OP *o|which
Exactly like C<XopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which)> but more
once. If you are using C<Perl_custom_op_xop> to retreive a
C<XOP *> from a C<OP *>, use the more efficient L</XopENTRYCUSTOM> instead.
=for apidoc Am||XopENTRYCUSTOM|const OP *o|which
Exactly like C<XopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which)> but more