This use of the ‘b’ type descriptor can be distinguished
from its use for builtin integral types (see Builtin Type Descriptors) because the character following the type descriptor is
always a digit, ‘(’, or ‘-’.
character*3is represented by ‘M-2;3’, where ‘-2’ is a reference to a character type (see Negative Type Numbers). I'm not sure how this differs from an array. This appears to be a Fortran feature. length is a bound, like those in range types; see Subranges.
In CHILL, if it is a bitstring instead of a set, also use the ‘S’
type attribute (see String Field).