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strictEquals.js
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// Your scientists were so preoccupied | |
// with whether or not they could, | |
// they didn't stop to think if they should. | |
// Like a === b | |
function strictEquals(a, b) { | |
if (Object.is(a, b)) { | |
// Same value. | |
// Is this NaN? | |
if (Object.is(a, NaN)) { // We already know a and b are the same, so it's enough to check a. | |
// Special case #1. | |
return false; | |
} else { | |
// They are equal! | |
return true; | |
} | |
} else { | |
// Different value. | |
// Are these 0 and -0? | |
if ( | |
(Object.is(a, 0) && Object.is(b, -0)) || | |
(Object.is(a, -0) && Object.is(b, 0)) | |
) { | |
// Special case #2. | |
return true; | |
} else { | |
// They are not equal! | |
return false; | |
} | |
} | |
} |
Yinboan
commented
Aug 30, 2023
I couldn't figure it out on my own so I looked at your version and tried to minimize (not simplify!) it to the best of my ability
const strictEquals = (a,b) => (Object.is(a,b)
? !Object.is(a, NaN)
: (Object.is(a, 0) && Object.is(b, -0)) || (Object.is(a, -0) && Object.is(b, 0)))
}
function strictEquals(a, b) {
if(Object.is(a, NaN) && Object.is(b, NaN)) return false;
if(Object.is(a, -0) && Object.is(b, 0)) return true;
if(Object.is(b, -0) && Object.is(a, 0)) return true;
return Object.is(a, b);
}
function strictEquals(a,b){
if(Number.isNaN(a)&&Number.isNaN(b)){
return false;
}
if(Number.isFinite(a) && Number.isFinite(b) && Math.abs(a)===0 && Math.abs(b)===0){
return true;
}
return Obejct.is(a,b);
}
const strictEquals = (a, b) => {
if (Object.is(a, NaN) && Object.is(NaN, b)) {
return false;
} else if (Object.is(a, 0) && Object.is(a, -0)) {
return true
} else if (Object.is(a, -0) && Object.is(b, 0)) {
return true
}
return Object.is(a,b)
}
const strictEquals = (a, b) => {
const isSameValue = Object.is(a, b)
// === behaves as same as Object.is() checks the both args are of same value or not
// edge cases
// 0 === -0 || -0 === 0 // true
// NaN === NaN // false
if(isSameValue && Object.is(a, NaN)){
return false
}
if((Object.is(a , 0) && Object.is(b, -0)) || (Object.is(a, -0) && Object.is(b, 0))){
return true
}
return isSameValue
}
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