! char.ax - character utility predicates

! bit - set of bits

  (bit `0).
  (bit `1).

! bitseq - set of bit sequences

  (bitseq %bits)<
    (bit* %bits).       ! we use mapping form defined elsewhere

! char - set of characters

  (char (`char %8bits))<
    (bitseq %8bits),
    (=length %8bits (* * * *  * * * *)).

! charseq - set of character sequences

  (charseq %chars)<
    (char* %chars).

! write - write a "tree" of characters to a flat char string

  (write %char (%char))<
    (char %char).
  (write () ()).
  (write (% $) %charstr)<
    (write % %charstr1),
    (write ($) %charstr2).
    (concat %charstr1 %charstr2 %charstr).