RE: [sv-bc] system functiions in constant expressions

1800 seems to specify implicitly or explicitly that the following
functions can be used in constant expressions:

12.3.3 constant function calls
"A constant function may call any system function that may be called in
a constant expression. This includes $bits and the array query
functions."

22.2 $typename
"When used as an elaboration time constant, the expression shall not
contain any hierarchical references or references to elements of dynamic
objects."

22.3 $bits
"The $bits function can be used as an elaboration time constant when
used on fixed-size data types; hence, it can be used in the declaration
of other data types, variables, or nets."

22.6 array query functions
"If the array identifier is a fixed-size array, these query functions
can be used as a constant function and passed as a parameter before
elaboration. These query functions can also be used on fixed-size type
identifiers, in which case it is always treated as a constant function."

However, the following functions would also seem to qualify:

22.4 $isunbounded
22.5 $shortrealtobits, $bitstoshortreal
22.9 $onehot, $onehot0, $isunknown, $countones

Shalom