1 | var $ = require('../internals/export');
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2 | var anObject = require('../internals/an-object');
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3 | var numberIsFinite = require('../internals/number-is-finite');
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4 | var createIteratorConstructor = require('../internals/create-iterator-constructor');
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5 | var InternalStateModule = require('../internals/internal-state');
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6 |
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7 | var SEEDED_RANDOM = 'Seeded Random';
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8 | var SEEDED_RANDOM_GENERATOR = SEEDED_RANDOM + ' Generator';
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9 | var setInternalState = InternalStateModule.set;
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10 | var getInternalState = InternalStateModule.getterFor(SEEDED_RANDOM_GENERATOR);
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11 | var SEED_TYPE_ERROR = 'Math.seededPRNG() argument should have a "seed" field with a finite value.';
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12 |
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13 | var $SeededRandomGenerator = createIteratorConstructor(function SeededRandomGenerator(seed) {
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14 | setInternalState(this, {
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15 | type: SEEDED_RANDOM_GENERATOR,
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16 | seed: seed % 2147483647
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17 | });
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18 | }, SEEDED_RANDOM, function next() {
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19 | var state = getInternalState(this);
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20 | var seed = state.seed = (state.seed * 1103515245 + 12345) % 2147483647;
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21 | return { value: (seed & 1073741823) / 1073741823, done: false };
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22 | });
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23 |
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24 |
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25 |
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26 |
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27 | $({ target: 'Math', stat: true, forced: true }, {
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28 | seededPRNG: function seededPRNG(it) {
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29 | var seed = anObject(it).seed;
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30 | if (!numberIsFinite(seed)) throw TypeError(SEED_TYPE_ERROR);
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31 | return new $SeededRandomGenerator(seed);
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32 | }
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33 | });
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