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rauschma/my-bool.js

Last active October 1, 2025 21:44
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my-bool.js
// Triggered by: https://fediverse.zachleat.com/@zachleat/115300801628689509
// Interesting inconsistency...
// The reason is probably backward compatibility:
// Truthiness checks are often used to answer the question “Is this value an object?”
class MyBool {
#bool;
constructor(bool) {
this.#bool = bool;
}
[Symbol.toPrimitive]() {
return this.#bool;
}
}
const myBool = new MyBool(false);
console.log("%j %j %j %j",
Boolean(myBool), // true
!!(myBool), // true
'' + myBool, // "false"
Number(myBool), // 0
);
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