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The concept of nothing in JavaScript (Crockford's idea of a better undefined)
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| nothing = new Proxy(Object.freeze(Object.create(null)), { | |
| get(target, property) { | |
| if (property === Symbol.toPrimitive) return () => undefined | |
| return nothing | |
| }, | |
| set() { | |
| return nothing | |
| } | |
| }) | |
| nothing.foo === nothing // true | |
| nothing.foo.bar.baz[42].qux // nothing (forever) | |
| nothing.foo = 42 // 42 (would ideally return nothing) | |
| nothing.foo // nothing | |
| typeof nothing // "object" | |
| Reflect.getPrototypeOf(nothing) // null | |
| // coerced to the primitive value undefined | |
| nothing + nothing // NaN | |
| nothing + true // NaN | |
| nothing + false // NaN | |
| nothing + 42 // NaN | |
| "hello, " + nothing // "hello, undefined" | |
| nothing + {} // "undefined[object Object]" | |
| nothing + [] // "undefined" | |
| nothing + 0n // TypeError: can't convert BigInt to number | |
| nothing + Symbol() // TypeError: can't convert symbol to number | |
| nothing / nothing // *implodes* (no, it's NaN) | |
| // it is unfortunately truthy because an object can't be falsy | |
| Boolean(nothing) // true |
I think that NaN should also be unified, so that 1/ 0 is nothing, and nothing + 1 is nothing.
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Crockford's idea of "null" as an immutable object that only ever returns itself:
https://www.youtube.com/watch?v=NPB34lDZj3E#t=12m23s
Of course, this implementation means nothing(…) if we can't override
undefineditself.But it's nice to see what we could've had! Or is it 🤔