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NumberToString.ts

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import { __TS__MathModf } from "./MathModf";

const radixChars = "0123456789abcdefghijklmnopqrstuvwxyz";

// https://www.ecma-international.org/ecma-262/10.0/index.html#sec-number.prototype.tostring

export function __TS__NumberToString(this: number, radix?: number): string {

if (radix === undefined || radix === 10 || this === Infinity || this === -Infinity || this !== this) {

return this.toString();

}

radix = Math.floor(radix);

if (radix < 2 || radix > 36) {

throw "toString() radix argument must be between 2 and 36";

}

let [integer, fraction] = __TS__MathModf(Math.abs(this));

let result = "";

if (radix === 8) {

result = string.format("%o", integer);

} else if (radix === 16) {

result = string.format("%x", integer);

} else {

do {

result = radixChars[integer % radix] + result;

integer = Math.floor(integer / radix);

} while (integer !== 0);

}

// https://github.com/v8/v8/blob/f78e8d43c224847fa56b3220a90be250fc0f0d6e/src/numbers/conversions.cc#L1221

if (fraction !== 0) {

result += ".";

let delta = 1e-16;

do {

fraction *= radix;

delta *= radix;

const digit = Math.floor(fraction);

result += radixChars[digit];

fraction -= digit;

// TODO: Round to even

} while (fraction >= delta);

}

if (this < 0) {

result = "-" + result;

}

return result;

}