[Pharo-users] Collection with memory?

[stepharo]

Hi

I need a collection that does the following:
col := #('a12' 'b12' 'a13' 'a14' 'c23' 'a16') asMyNewCollection.
col findFirst: [:each | each first = $a]
    > a12
col findFirst: [:each | each first = $a]
    > a13

Do you know a collection that would work?
So I have the impression that such behavoir could be defined with a kind 
of methods wrapper.

Stef