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- export default function parse(input) {
- input = input.toUpperCase();
- var splitIndex = input.indexOf("P");
- var mantissa, exponent;
-
- if (splitIndex !== -1) {
- mantissa = input.substring(0, splitIndex);
- exponent = parseInt(input.substring(splitIndex + 1));
- } else {
- mantissa = input;
- exponent = 0;
- }
-
- var dotIndex = mantissa.indexOf(".");
-
- if (dotIndex !== -1) {
- var integerPart = parseInt(mantissa.substring(0, dotIndex), 16);
- var sign = Math.sign(integerPart);
- integerPart = sign * integerPart;
- var fractionLength = mantissa.length - dotIndex - 1;
- var fractionalPart = parseInt(mantissa.substring(dotIndex + 1), 16);
- var fraction = fractionLength > 0 ? fractionalPart / Math.pow(16, fractionLength) : 0;
-
- if (sign === 0) {
- if (fraction === 0) {
- mantissa = sign;
- } else {
- if (Object.is(sign, -0)) {
- mantissa = -fraction;
- } else {
- mantissa = fraction;
- }
- }
- } else {
- mantissa = sign * (integerPart + fraction);
- }
- } else {
- mantissa = parseInt(mantissa, 16);
- }
-
- return mantissa * (splitIndex !== -1 ? Math.pow(2, exponent) : 1);
- }
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