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add Math.sumPrecise
https://github.com/tc39/proposal-math-sum
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‎packages/core-js-compat/src/data.mjs

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@@ -2258,6 +2258,8 @@ export const data = {
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},
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'esnext.math.signbit': {
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},
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'esnext.math.sum-precise': {
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},
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// TODO: Remove from `core-js@4`
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'esnext.math.umulh': {
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},

‎packages/core-js-compat/src/modules-by-versions.mjs

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@@ -245,6 +245,7 @@ export default {
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'es.set.is-superset-of.v2',
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'es.set.symmetric-difference.v2',
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'es.set.union.v2',
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'esnext.math.sum-precise',
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'web.url.parse',
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],
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};

‎packages/core-js/full/math/index.js

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@@ -1,5 +1,6 @@
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'use strict';
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var parent = require('../../actual/math');
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require('../../modules/es.array.iterator');
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require('../../modules/esnext.math.clamp');
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require('../../modules/esnext.math.deg-per-rad');
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require('../../modules/esnext.math.degrees');
@@ -9,6 +10,7 @@ require('../../modules/esnext.math.radians');
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require('../../modules/esnext.math.scale');
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require('../../modules/esnext.math.seeded-prng');
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require('../../modules/esnext.math.signbit');
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require('../../modules/esnext.math.sum-precise');
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// TODO: Remove from `core-js@4`
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require('../../modules/esnext.math.iaddh');
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require('../../modules/esnext.math.isubh');

‎packages/core-js/full/math/sum-precise.js

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'use strict';
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require('../../modules/es.array.iterator');
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require('../../modules/esnext.math.sum-precise');
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var path = require('../../internals/path');
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module.exports = path.Math.sumPrecise;

‎packages/core-js/modules/esnext.math.sum-precise.js

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'use strict';
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// based on Shewchuk's algorithm for exactly floating point addition
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// adapted from https://github.com/tc39/proposal-math-sum/blob/3513d58323a1ae25560e8700aa5294500c6c9287/polyfill/polyfill.mjs
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var $ = require('../internals/export');
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var uncurryThis = require('../internals/function-uncurry-this');
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var iterate = require('../internals/iterate');
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var $RangeError = RangeError;
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var $TypeError = TypeError;
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var $Infinity = Infinity;
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var $NaN = NaN;
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var abs = Math.abs;
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var pow = Math.pow;
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var push = uncurryThis([].push);
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var POW_2_1023 = pow(2, 1023);
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var MAX_SAFE_INTEGER = pow(2, 53) - 1;
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// exponent 11111111110, significand all 1s
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var MAX_DOUBLE = 1.79769313486231570815e+308; // 2 ** 1024 - 2 ** (1023 - 52)
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// exponent 11111111110, significand all 1s except final 0
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var PENULTIMATE_DOUBLE = 1.79769313486231550856e+308; // 2 ** 1024 - 2 * 2 ** (1023 - 52)
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// exponent 11111001010, significand all 0s
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var MAX_ULP = MAX_DOUBLE - PENULTIMATE_DOUBLE; // 1.99584030953471981166e+292, <- 2 ** (1023 - 52)
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var NOT_A_NUMBER = {};
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var MINUS_INFINITY = {};
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var PLUS_INFINITY = {};
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var MINUS_ZERO = {};
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var FINITE = {};
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// prerequisite: abs(x) >= abs(y)
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var twosum = function (x, y) {
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var hi = x + y;
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var lo = y - (hi - x);
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return { hi: hi, lo: lo };
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};
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// `Math.sumPrecise` method
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// https://github.com/tc39/proposal-math-sum
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$({ target: 'Math', stat: true, forced: true }, {
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// eslint-disable-next-line max-statements -- ok
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sumPrecise: function sumPrecise(items) {
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var numbers = [];
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var count = 0;
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var state = MINUS_ZERO;
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iterate(items, function (n) {
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if (++count >= MAX_SAFE_INTEGER) throw new $RangeError('Maximum allowed index exceeded');
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if (typeof n != 'number') throw new $TypeError('Value is not a number');
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if (state !== NOT_A_NUMBER) {
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// eslint-disable-next-line no-self-compare -- NaN check
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if (n !== n) state = NOT_A_NUMBER;
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else if (n === $Infinity) state = state === MINUS_INFINITY ? NOT_A_NUMBER : PLUS_INFINITY;
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else if (n === -$Infinity) state = state === PLUS_INFINITY ? NOT_A_NUMBER : MINUS_INFINITY;
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else if ((n !== 0 || (1 / n) === $Infinity) && (state === MINUS_ZERO || state === FINITE)) {
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state = FINITE;
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push(numbers, n);
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}
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}
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});
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switch (state) {
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case NOT_A_NUMBER: return $NaN;
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case MINUS_INFINITY: return -$Infinity;
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case PLUS_INFINITY: return $Infinity;
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case MINUS_ZERO: return -0;
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}
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var partials = [];
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var overflow = 0; // conceptually 2**1024 times this value; the final partial is biased by this amount
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var x, y, sum, hi, lo, tmp;
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for (var i = 0; i < numbers.length; i++) {
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x = numbers[i];
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var actuallyUsedPartials = 0;
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for (var j = 0; j < partials.length; j++) {
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y = partials[j];
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if (abs(x) < abs(y)) {
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tmp = x;
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x = y;
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y = tmp;
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}
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sum = twosum(x, y);
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hi = sum.hi;
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lo = sum.lo;
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if (abs(hi) === $Infinity) {
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var sign = hi === $Infinity ? 1 : -1;
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overflow += sign;
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x = (x - (sign * POW_2_1023)) - (sign * POW_2_1023);
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if (abs(x) < abs(y)) {
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tmp = x;
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x = y;
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y = tmp;
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}
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sum = twosum(x, y);
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hi = sum.hi;
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lo = sum.lo;
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}
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if (lo !== 0) {
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partials[actuallyUsedPartials] = lo;
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actuallyUsedPartials += 1;
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}
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x = hi;
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}
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partials.length = actuallyUsedPartials;
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if (x !== 0) partials[partials.length] = x;
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}
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// compute the exact sum of partials, stopping once we lose precision
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var n = partials.length - 1;
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hi = 0;
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lo = 0;
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if (overflow !== 0) {
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var next = n >= 0 ? partials[n] : 0;
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n -= 1;
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if (abs(overflow) > 1 || (overflow > 0 && next > 0) || (overflow < 0 && next < 0)) {
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return overflow > 0 ? $Infinity : -$Infinity;
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}
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// here we actually have to do the arithmetic
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// drop a factor of 2 so we can do it without overflow
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// assert(abs(overflow) === 1)
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sum = twosum(overflow * POW_2_1023, next / 2);
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hi = sum.hi;
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lo = sum.lo;
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lo *= 2;
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if (abs(2 * hi) === $Infinity) {
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// rounding to the maximum value
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if (hi > 0) {
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return (hi === POW_2_1023 && lo === -(MAX_ULP / 2) && n >= 0 && partials[n] < 0) ? MAX_DOUBLE : $Infinity;
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} return (hi === -POW_2_1023 && lo === (MAX_ULP / 2) && n >= 0 && partials[n] > 0) ? -MAX_DOUBLE : -$Infinity;
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}
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if (lo !== 0) {
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partials[n + 1] = lo;
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n += 1;
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lo = 0;
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}
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hi *= 2;
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}
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while (n >= 0) {
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x = hi;
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y = partials[n];
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n -= 1;
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sum = twosum(x, y);
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hi = sum.hi;
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lo = sum.lo;
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if (lo !== 0) break;
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}
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if (n >= 0 && ((lo < 0.0 && partials[n] < 0.0) || (lo > 0.0 && partials[n] > 0.0))) {
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y = lo * 2.0;
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x = hi + y;
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if (y === x - hi) hi = x;
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}
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return hi;
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}
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});

‎packages/core-js/proposals/math-sum.js

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'use strict';
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// https://github.com/tc39/proposal-math-sum
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require('../modules/esnext.math.sum-precise');

‎packages/core-js/stage/2.7.js

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'use strict';
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var parent = require('./3');
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require('../proposals/math-sum');
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require('../proposals/promise-try');
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module.exports = parent;

‎tests/compat/tests.js

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@@ -1767,6 +1767,9 @@ GLOBAL.tests = {
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'esnext.math.signbit': function () {
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return Math.signbit;
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},
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'esnext.math.sum-precise': function () {
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return Math.sumPrecise;
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},
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'esnext.number.from-string': function () {
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return Number.fromString;
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},

‎tests/entries/unit.mjs

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@@ -796,6 +796,7 @@ for (PATH of ['core-js-pure', 'core-js']) {
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ok(load(NS, 'math/scale')(3, 1, 2, 1, 2) === 3);
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ok(typeof load(NS, 'math/seeded-prng')({ seed: 42 }).next().value === 'number');
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ok(load(NS, 'math/signbit')(-2) === true);
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ok(load(NS, 'math/sum-precise')([1, 2, 3]) === 6);
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ok(load(NS, 'math/umulh')(0xFFFFFFFF, 7) === 6);
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ok(load(NS, 'map/of')([1, 2], [3, 4]) instanceof Map);
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ok(load(NS, 'map/reduce')(new Map([[1, 2], [2, 3], [3, 4]]), (a, b) => a + b) === 9);
@@ -938,6 +939,7 @@ for (PATH of ['core-js-pure', 'core-js']) {
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load('proposals/map-upsert-stage-2');
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load('proposals/math-extensions');
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load('proposals/math-signbit');
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load('proposals/math-sum');
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load('proposals/number-from-string');
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load('proposals/number-range');
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load('proposals/object-from-entries');

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