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 // For and if clauses can nest without limit in comprehensions.  This is

 // unlike JS 1.8 comprehensions, which can only have one trailing "if"

 // clause.

 function* range(start, end) {

   for (var n = start; n < end; n++)

     yield n;

 }

 function primesBetween6And25() {

   return [for (n of range(6, 25)) if (n % 2) if (n % 3) if (n % 5) n];

 }

 assertDeepEq(primesBetween6And25(), [7,11,13,17,19,23]);

 function countUpToEvens(limit) {

   return [for (n of range(0, limit)) if (!(n % 2)) for (m of range(0, n)) m]

 }

 assertDeepEq(countUpToEvens(7), [0,1,0,1,2,3,0,1,2,3,4,5]);

 reportCompare(null, null, "test");