javascript - Converting between int[ish] and double[ish] in asm.js - Stack Overflow

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If I need to, say, find the the integer part and the fractional part of a number within an asm.js module, how do I do it? None of the standard operators convert between intish and doubleish types; even Math.floor returns a double, and its result can't be coerced to an int.

var floor = stdlib.Math.floor;

function(n) {
    n = +n;
    var a = 0;
    a = floor(n)|0; // fails: "Operands to bitwise ops must be intish"
    var b = 0.0;
    b = +(n-a); // would fail if piler got to here
    return;
}

If I need to, say, find the the integer part and the fractional part of a number within an asm.js module, how do I do it? None of the standard operators convert between intish and doubleish types; even Math.floor returns a double, and its result can't be coerced to an int.

var floor = stdlib.Math.floor;

function(n) {
    n = +n;
    var a = 0;
    a = floor(n)|0; // fails: "Operands to bitwise ops must be intish"
    var b = 0.0;
    b = +(n-a); // would fail if piler got to here
    return;
}

• javascript
• firefox
• asm.js

Share Improve this question Follow asked May 21, 2013 at 22:25 ZachBZachB 15.5k55 gold badges6666 silver badges9393 bronze badges

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1 Answer 1

Sorted by: Reset to default 10

Vyacheslav Egorov (twitter:@mraleph) says: use ~~ to coerce to an int. Special validation case: http://asmjs/spec/latest/#unaryexpression

a = ~~floor(n); // success!

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