-> CAPLIB APL2 doesn't provide for scalar character variables.  The lowest
   rank a character variable can have is 1 (a vector).  Thus, expressions
   like -
   
   	display ''%''
     
   will get a domain error, whereas IBM's APL2 would produce -

     +@+
     |0|
     +~+

-> The Binomial function, described on page 66, indicates that L!R,
   where L and R are negative integers, and R-L is negative (i.e. R < L),
   the binomial function returns the APL expression (-1*R-L)x(+1)!(|L+1).
   This is incorrect. Find out if there's an update to the manual, or
   enter a query on IBMIN.  Then update binom.c and binomp.c, and
   rerun sam229.txt.

-> Implement the binomial function, as described on page 66, for
   imaginary numbers.

-> Figure out what "phase" means, and implement 12 O r, where r is complex.
   See pages 80, 84, and 93.  Finish verifying sam234.txt for the examples
   on page 84.

-> Lrl (random link), as shown on page 89, is not yet implemented.