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var $ = require('../internals/export');
var anObject = require('../internals/an-object');
var numberIsFinite = require('../internals/number-is-finite');
var createIteratorConstructor = require('../internals/create-iterator-constructor');
var InternalStateModule = require('../internals/internal-state');
var SEEDED_RANDOM = 'Seeded Random';
var SEEDED_RANDOM_GENERATOR = SEEDED_RANDOM + ' Generator';
var setInternalState = InternalStateModule.set;
var getInternalState = InternalStateModule.getterFor(SEEDED_RANDOM_GENERATOR);
var SEED_TYPE_ERROR = 'Math.seededPRNG() argument should have a "seed" field with a finite value.';
var $SeededRandomGenerator = createIteratorConstructor(function SeededRandomGenerator(seed) {
setInternalState(this, {
type: SEEDED_RANDOM_GENERATOR,
seed: seed % 2147483647
});
}, SEEDED_RANDOM, function next() {
var state = getInternalState(this);
var seed = state.seed = (state.seed * 1103515245 + 12345) % 2147483647;
return { value: (seed & 1073741823) / 1073741823, done: false };
});
// `Math.seededPRNG` method
// https://github.com/tc39/proposal-seeded-random
// based on https://github.com/tc39/proposal-seeded-random/blob/78b8258835b57fc2100d076151ab506bc3202ae6/demo.html
$({ target: 'Math', stat: true, forced: true }, {
seededPRNG: function seededPRNG(it) {
var seed = anObject(it).seed;
if (!numberIsFinite(seed)) throw TypeError(SEED_TYPE_ERROR);
return new $SeededRandomGenerator(seed);
}
});