WeakMap-constructor-generator-1.js

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// The argument to WeakMap can be a generator.

var k1 = {};

var v1 = 42;

var k2 = {};

var v2 = 43;

var k3 = {};

var done = false;

function* data() {

  yield [k1, v1];

  yield [k2, v2];

  done = true;

};

m = new WeakMap(data());

assertEq(done, true);  // the constructor consumes the argument

assertEq(m.has(k1), true);

assertEq(m.has(k2), true);

assertEq(m.has(k3), false);

assertEq(m.get(k1), v1);

assertEq(m.get(k2), v2);

assertEq(m.get(k3), undefined);