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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);
- }
- });
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