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by ynniv 4998 days ago
a good time to point out that calling Object() without "new" returns a new object. This is often unexpected when creating inheritance schemes that chain the parent constructor.

https://github.com/documentcloud/backbone/pull/1269

1 comments

Not sure I understand your comment, given the link you gave.

IMHO the return value of calling `Object()` without parameters is exactly what one would expect. Calling it w/ parameters is what I think causes surprising behavior

    var x = {a: 2}
    console.log(x === x)             // true
    console.log(Object(x) === x)     // true
    console.log(new Object(x) === x) // true
For the `Object.call(x)` case, I'd expect it to return a new object (and not x), for the same reason I'd expect [].slice.call(arguments) to return a new array (and not arguments).
[].slice.call(arguments) returning a new argument is fundamentally different because you would not want x.slice(1,2) to modify x in order to produce an appropriate sublist to return. Perhaps it's just me, but I expect a constructor to initialize "this" (optionally returning "this"), but not returning {};
Disagree. To illustrate:

    window.test = 2
    var b = Object.call(window) //this is the same as `var b = window.Object()` and therefore the same as `var b = Object()`
    assert(b.test == 2) //why should this be true?