Re: Non-constructible constructors and Arrays

On 8/3/11, Allen Wirfs-Brock <> wrote:
> On Aug 2, 2011, at 4:47 PM, Cameron McCormack wrote:
>> On 3/08/11 4:04 AM, Allen Wirfs-Brock wrote:
>>> Well, it's inherent in the ES specification's algorithm for each
>>> method whether or not it mutates its this value.  We might consider
>>> adding a non-normative note that further identifies such methods as
>>> mutating or non-mutating but that doesn't really add any additional
>>> information that isn't already available to browser implementors.
>> It's probably "obvious" in some sense, but it's the kind of thing I don't
>> really like to leave open to interpretation.
> I won't argue one way or another about obviousness, but the ES51 spec is
> certainly precise WRT which of these methods mutate and which don't. There
> is no room for interpretation but of course erroneous readings are always
> possible.
Does [1].reverse() mutate the object that it's called on?
Unambiguously, no, right? So you have methods that will throw
sometimes and not others.

If you tag these methods as mutating non/mutating, any system using
them can "fail fast."

Received on Wednesday, 3 August 2011 17:24:36 UTC