1
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export default function parse(input) {
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2
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input = input.toUpperCase();
|
3
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var splitIndex = input.indexOf("P");
|
4
|
var mantissa, exponent;
|
5
|
|
6
|
if (splitIndex !== -1) {
|
7
|
mantissa = input.substring(0, splitIndex);
|
8
|
exponent = parseInt(input.substring(splitIndex + 1));
|
9
|
} else {
|
10
|
mantissa = input;
|
11
|
exponent = 0;
|
12
|
}
|
13
|
|
14
|
var dotIndex = mantissa.indexOf(".");
|
15
|
|
16
|
if (dotIndex !== -1) {
|
17
|
var integerPart = parseInt(mantissa.substring(0, dotIndex), 16);
|
18
|
var sign = Math.sign(integerPart);
|
19
|
integerPart = sign * integerPart;
|
20
|
var fractionLength = mantissa.length - dotIndex - 1;
|
21
|
var fractionalPart = parseInt(mantissa.substring(dotIndex + 1), 16);
|
22
|
var fraction = fractionLength > 0 ? fractionalPart / Math.pow(16, fractionLength) : 0;
|
23
|
|
24
|
if (sign === 0) {
|
25
|
if (fraction === 0) {
|
26
|
mantissa = sign;
|
27
|
} else {
|
28
|
if (Object.is(sign, -0)) {
|
29
|
mantissa = -fraction;
|
30
|
} else {
|
31
|
mantissa = fraction;
|
32
|
}
|
33
|
}
|
34
|
} else {
|
35
|
mantissa = sign * (integerPart + fraction);
|
36
|
}
|
37
|
} else {
|
38
|
mantissa = parseInt(mantissa, 16);
|
39
|
}
|
40
|
|
41
|
return mantissa * (splitIndex !== -1 ? Math.pow(2, exponent) : 1);
|
42
|
}
|