-- Solutions to exercises from the Central European Functional Programming summer school
-- July 4th-16th 2005

-- Write two separate Hume programs that merge three inputs into
-- a single output fairly and unfairly, respectively.  Test your programs
-- on the same input values.

-- HW-Hume solution

-- Note 
--   a) the use of '*' to avoid reading from the specified input;
--   b) the use of input and output streams

-- Kevin Hammond, 5th July 2005


program

 box merge
 in (cin1,cin2,cin3::char)
 out (cout::char)
 fair
    (c,*,*)  -> c
  | (*,c,*)  -> c
  | (*,*,c)  -> c
  ;

 stream stdout to "std_out";

 stream merge1 from "merge1.txt";
 stream merge2 from "merge2.txt";
 stream merge3 from "merge3.txt";

 wire merge (merge1,merge2,merge3)
             (stdout);