From jmc at r-project.org  Fri Aug  5 19:22:32 2011
From: jmc at r-project.org (John Chambers)
Date: Fri, 05 Aug 2011 10:22:32 -0700
Subject: [Rd] initFields() method no longer coerces arguments in R-devel
In-Reply-To: <050B398D-DF57-49E5-8DB3-9DCB3D33E984@r-project.org>
References: <CAM9CR=2fg_5io9xGZnW86JB-51BOTqxH_Ui=gPh5odciPa7eGA@mail.gmail.com>
	<050B398D-DF57-49E5-8DB3-9DCB3D33E984@r-project.org>
Message-ID: <4E3C26D8.3030300@r-project.org>

There is also an item in the NEWS file:

     Field assignments in reference classes are now consistent with 
slots in S4 classes: the assigned value must come from the declared 
class (if any) for the field or from a subclass.

On 8/5/11 7:24 AM, Simon Urbanek wrote:
> It's worth actually reading the list you post to ...
> http://r.789695.n4.nabble.com/Reference-classes-assignments-to-fields-td3708168.html
>
>
> On Aug 5, 2011, at 6:41 AM, Jon Clayden wrote:
>
>> Dear all,
>>
>> I've just had a package update bounced from CRAN because of a recent
>> change in R-devel which seems to affect the behaviour of the
>> initFields() reference class method. (The change must be very recent
>> because I tested the package on a week-old build of R-devel.) It seems
>> that the method no longer coerces its arguments to the expected type
>> of each field. For a simple example:
>>
>>> Foo<- setRefClass("Foo", fields=list(number="integer"), methods=list(initialize=function (number = NULL) initFields(number=number)))
>>> Foo$new()
>> Error in function (value)  :
>>   invalid replacement for field ?number?, should be from class
>> ?integer? or a subclass (was class ?NULL?)
>>
>> (This used to work, with "number" being set to "integer(0)"). In fact
>> it is now extremely strict, not even allowing a double literal which
>> is equal to an integer:
>>
>>> Foo$new(number=1)
>> Error in function (value)  :
>>   invalid replacement for field ?number?, should be from class
>> ?integer? or a subclass (was class ?numeric?)
>>
>> I don't see anything about this in the NEWS, so I was wondering if I
>> could get clarification on whether this is now the intended behaviour,
>> before I further modify the package. I must say that this will be a
>> bit of a pain to "correct"...
>>
>> All the best,
>> Jon
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>
>>
> ______________________________________________
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>



[Rd] initFields() method no longer coerces arguments in R-devel
John Chambers