const as default for variables

[deadalnix via Digitalmars-d]

On Monday, 16 March 2015 at 00:07:32 UTC, Walter Bright wrote:
> On 3/15/2015 1:09 PM, deadalnix wrote:
>> On Sunday, 15 March 2015 at 07:44:50 UTC, Walter Bright wrote:
>>> "const ref" can tell the optimizer that that path for a ref 
>>> counted object
>>> cannot alter its ref count.
>>
>> That is not clear why. const ref is supposed to protect 
>> against escaping when
>> ref does not ?
>
> Passing rc objects by const ref, for example, precludes the 
> disastrous cases enumerated in the "RCArray is unsafe" thread.

That is true.