Immutable Red-Black trees

[Craig Dillabaugh]

On Tuesday, 26 November 2013 at 01:21:49 UTC, Craig Dillabaugh 
wrote:
> On Tuesday, 26 November 2013 at 00:28:34 UTC, bearophile wrote:
clip
>>
>> Bye,
>> bearophile
>
> What do you mean by an 'immutable' data structure.  The linked 
> article talks about Persistent data structures.  Are these the 
> same thing?
>
> When I saw "Immutable" I figured it didn't support 
> insertion/deletion - which would sort eliminate the need for a 
> Red-Black tree anyways.

While I am at it, I might as well ask another question.  How is 
it that your 'insert' function is const?  I thought I understood 
const, but apparently not!

Cheers