44 lines
1.7 KiB
Plaintext
Executable File
44 lines
1.7 KiB
Plaintext
Executable File
"use strict";
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
|
exports.ComputeExponent = void 0;
|
|
var utils_1 = require("../utils");
|
|
var ComputeExponentForMagnitude_1 = require("./ComputeExponentForMagnitude");
|
|
var FormatNumericToString_1 = require("./FormatNumericToString");
|
|
/**
|
|
* The abstract operation ComputeExponent computes an exponent (power of ten) by which to scale x
|
|
* according to the number formatting settings. It handles cases such as 999 rounding up to 1000,
|
|
* requiring a different exponent.
|
|
*
|
|
* NOT IN SPEC: it returns [exponent, magnitude].
|
|
*/
|
|
function ComputeExponent(numberFormat, x, _a) {
|
|
var getInternalSlots = _a.getInternalSlots;
|
|
if (x === 0) {
|
|
return [0, 0];
|
|
}
|
|
if (x < 0) {
|
|
x = -x;
|
|
}
|
|
var magnitude = (0, utils_1.getMagnitude)(x);
|
|
var exponent = (0, ComputeExponentForMagnitude_1.ComputeExponentForMagnitude)(numberFormat, magnitude, {
|
|
getInternalSlots: getInternalSlots,
|
|
});
|
|
// Preserve more precision by doing multiplication when exponent is negative.
|
|
x = exponent < 0 ? x * Math.pow(10, -exponent) : x / Math.pow(10, exponent);
|
|
var formatNumberResult = (0, FormatNumericToString_1.FormatNumericToString)(getInternalSlots(numberFormat), x);
|
|
if (formatNumberResult.roundedNumber === 0) {
|
|
return [exponent, magnitude];
|
|
}
|
|
var newMagnitude = (0, utils_1.getMagnitude)(formatNumberResult.roundedNumber);
|
|
if (newMagnitude === magnitude - exponent) {
|
|
return [exponent, magnitude];
|
|
}
|
|
return [
|
|
(0, ComputeExponentForMagnitude_1.ComputeExponentForMagnitude)(numberFormat, magnitude + 1, {
|
|
getInternalSlots: getInternalSlots,
|
|
}),
|
|
magnitude + 1,
|
|
];
|
|
}
|
|
exports.ComputeExponent = ComputeExponent;
|