[Haskell-cafe] Collections

[Andrew Coppin]

Derek Elkins wrote:
> On Tue, 2007-06-19 at 18:49 -0400, Brandon S. Allbery KF8NH wrote:
>   
>> Haskell is, in many ways, a descendant of Lisp.  This does tend to  
>> lead to lists being *the* collection type, in my experience:  sure,  
>> others get used, but lists are the ones you see in examples and such.
>>     
>
> Not in my experience.  Certainly lists are used all over the place*, but
> I rarely see them abused.  Also, "lists" aren't lists in Lisp, they're
> more akin to rose-trees (or going the other way, there are only pairs in
> Lisp). 
>   

http://xkcd.com/c224.html

> In practice, almost all Haskell programs use custom defined algebraic
> data types which are usually tree like.  Declaring and using data types
> is easier in Haskell than it is in almost any other language.
>   

True...

> * As others have mentioned, lists represent loops and loops are
> extremely common in programming in general.
>   

Um... surely *every* collection type represents a loop?