Out contracts: how to refer to objects' start state

[Adam D. Ruppe]

On Sunday, 26 May 2013 at 01:12:35 UTC, Andrei Alexandrescu wrote:
> On 5/25/13 9:03 PM, Andrej Mitrovic wrote:
>> On 5/26/13, Andrei Alexandrescu<SeeWebsiteForEmail at erdani.org>
>>>    in { auto oldLen = this.length; }
>> out { assert(this.length == in.oldLen + 1); }

> Since every in.xyz expression could access an arbitrary method 
> of the old object,

Here, in.oldLen refers to the local variable you defined in the 
in{} scope, as opposed to plain oldLen which would be searing the 
out{} scope.