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Addressed some of the issues brought up by @jdalton in https://gist.g…
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@kriskowal
kriskowal committed Aug 9, 2011
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9 comments on commit 21c880d

@tkissing
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Is there a specific reason (aside from saving bytes) that you are using 1/0 instead of Infinity or Number.POSITIVE_INFINITY ?

@michaelficarra
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@tkissing: 1/0 always produces an Infinity value. Similar to undefined and NaN, Infinity is a writeable (in most cases) global variable that initially contains an Infinity value.

@paulmillr
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I'd say not 'in the most cases', but only in old IEs.

http://es5.github.com/x15.1.html#x15.1.1.2

@michaelficarra
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@paulmillr: I don't know of an interpreter that disallows writing to Infinity outside strict mode. They all implement ES3 15.1.1.2.

The initial value of Infinity is +∞ (section 8.5). This property has the attributes { DontEnum, DontDelete }.

@tkissing
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@kitcambridge Which environment allows overriding of Number.POSITIVE_INFINITY? Infinity is a property of the global object, so I understand the objection for that. But Number.POSITIVE_INFINITY should be a true constant.

@michaelficarra
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@tkissing: While you're right about the POSITIVE_INFINITY property, that's only useful if we can guarantee we have a reference to the original Number constructor, which is writeable...

@tkissing
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Doh. Thanks for the explanations everyone. Guess I will have to live with the warnings during build then (or just see if I can live without any of the shims that use toInteger and remove that code).

@paulmillr
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@michaelficarra just checked latest Spidermonkey, Nitro, Carakan & v8 in stable browsers -- no strict mode needed, Inf & undefined can't be redefined.

@michaelficarra
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@paulmillr:

A fairly recent version of node (v8):

$ node --version
v0.6.7
$ node
> Infinity = 4
4
> Infinity
4

And I installed latest stable node just in case:

$ node --version
v0.6.12
$ node
> Infinity = 4
4
> Infinity
4

And last time I checked v8 through chrome that behaviour existed, but you're right: it has now changed for me as well (using the latest Chrome beta build).

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