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

Actually, 1364 does not say that the function needs to depend only on
the *values* of its arguments, it just says it needs to depend only on
the arguments, which can include their types as well.

> Some of the system functions, such as $bits and $dimensions, are not
> pure in a strict sense.  They don't depend only on the values of their
> arguments.  They depend on side-attributes of their arguments, such
> as their type.  Regarding them as pure can introduce new kinds of
> issues with dependencies that were not considered when allowing all
> "pure" functions.

Shalom