Hello List,

In "The LaTeX3 Sources" document it says (on p. 296,
Released 2018-12-12):
"Older versions of expl3 divided up primitives by “source”:
that becomes very tricky with multiple parallel engine
developments, so has been dropped. To cover the transition,
we provide the older names here for a limited period (until
the end of019)."

Does this mean one should avoid using functions such as
"\etex_iffontchar:D"?
If yes, are there any alternative to such commands?

Furthermore, in "The expl3 package and LaTeX3 programming"
document it says (on page 7, Released 2018-12-12):
"D This means: Do not use. This special case is used for TEX
primitives. Programmers outside the kernel team should not use
these functions!"

Again, which function should a programmer who is not a member
of kernel team use instead of "\etex_iffontchar:D"?

Thanks,
Tisha