implementation of python's chain() method in Chapel

example6Chain.chpl

use RangeChunk;

iter compress(array, trutharray) {
  for (i,j) in zip(array, trutharray) {
    if j {
      yield i;
    }
  }
}


// leader
iter compress(param tag: iterKind, array, trutharray)
    where tag == iterKind.leader {
    var numTasks = here.maxTaskPar;
    var Range = array.domain.low..array.domain.high;
    coforall tid in 0..#numTasks {
        var nowRange = chunk(Range, numTasks, tid);
        yield (nowRange, );
    }
}

// follower
iter compress(param tag: iterKind, array, trutharray, followThis)
    where tag == iterKind.follower && followThis.size == 1 {
    var nowRange = followThis(1);
    for i in nowRange {
        if trutharray[i] {
            yield array[i];
        }
    }
}




var used =  [1,2,3,4,5,6,7,8,9,10,11,12];
var truth = [1,0,0,0,1,1,0,1,0,1, 1, 0];

writeln("paraller");
forall i in compress(used, truth) {
    writeln(i);
}

writeln("serial");
for i in compress(used, truth) {
    writeln(i);
}