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Immutable Lists

What's the best way to achieve this, or is this a bad idea?

Feb 12 '07
14 6139
"Peter Bromberg [C# MVP]" <pb*******@yaho o.yabbadabbadoo .coma écrit dans
le message de news: 1D************* *************** **...icrosof t.com...

| Did their homework after all.
| Nice.
| Peter

| "Laura T." wrote:
|
| Supported yes, but also correctly implemented to be really
| readonlycollect ion, for example:
| >
>>>>>>
| So it really remains "immutable" .

Shucks! you saw through my little ploy :-)

Joanna

--
Joanna Carter [TeamB]
Consultant Software Engineer
Feb 12 '07 #11
But ReadoOnlyCollec tionBase is within the System.Collecti ons
namespace, not System.Collecti ons.Generic.

So if I want my immutable list to be Generic, I guess I should
implement ICollection<T>, IEnumerable<T>, ICollection, IEnumerable and
do this by hand?

Feb 13 '07 #12
There is a ReadOnlyCollect ion<Tin one of the system.collecti ons
namespaces. I use it, but don't remember off-hand which namespace.

Mike Ober.

<ph********@gma il.comwrote in message
news:11******** *************@v 33g2000cwv.goog legroups.com...
But ReadoOnlyCollec tionBase is within the System.Collecti ons
namespace, not System.Collecti ons.Generic.

So if I want my immutable list to be Generic, I guess I should
implement ICollection<T>, IEnumerable<T>, ICollection, IEnumerable and
do this by hand?


Feb 13 '07 #13
Yes, it it in the ObjectModel namespace (who knows why).
The only problem with it is that it does not lend for nice inheritance,
because ReadOnlyCollect ion<Thas only one constructor that needs a IList as
a parameter.. it is, afterall, ReadOnly..

"Michael D. Ober" <obermd.@.alum. mit.edu.nospamh a scritto nel messaggio
news:Vv******** ********@newsre ad1.news.pas.ea rthlink.net...
There is a ReadOnlyCollect ion<Tin one of the system.collecti ons
namespaces. I use it, but don't remember off-hand which namespace.

Mike Ober.

<ph********@gma il.comwrote in message
news:11******** *************@v 33g2000cwv.goog legroups.com...
>But ReadoOnlyCollec tionBase is within the System.Collecti ons
namespace, not System.Collecti ons.Generic.

So if I want my immutable list to be Generic, I guess I should
implement ICollection<T>, IEnumerable<T>, ICollection, IEnumerable and
do this by hand?



Feb 13 '07 #14
:-) There is a reason. I had that problem years ago. I was supposed to
implement a static collection so I derived it from ReadOnlyCollect ionBase.
Just a very light wrapper. But I ignored the IList interface..
After a while my collection "had learned" the capability to write too..
That's why when the generic one come out, I was eager to check if they did
the same bad thing as with ReadOnlyCollect ionBase...
As Peter said, the second time, you need to do your homework properly.
"Joanna Carter [TeamB]" <jo****@not.for .spamha scritto nel messaggio
news:u5******** ******@TK2MSFTN GP06.phx.gbl...
"Peter Bromberg [C# MVP]" <pb*******@yaho o.yabbadabbadoo .coma écrit dans
le message de news: 1D************* *************** **...icrosof t.com...

| Did their homework after all.
| Nice.
| Peter

| "Laura T." wrote:
|
| Supported yes, but also correctly implemented to be really
| readonlycollect ion, for example:
| >
>>>>>>>
| So it really remains "immutable" .

Shucks! you saw through my little ploy :-)

Joanna

--
Joanna Carter [TeamB]
Consultant Software Engineer


Feb 13 '07 #15

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