[Haskell-beginners] Is it possible to check list length at compile time?

[David McBride]

It is possible to go part of the way.  See for example, the NonEmpty type
in the semigroups package.  It is a list that always has at least one
element by restricting the operations you can do to the type without
turning it into a normal list.  You could easily adapt that solution to a
sixteen element list, but it might not be a reasonable amount of trouble to
go through.

On Tue, Mar 17, 2015 at 1:26 PM, Kelong Cong <kelongcong at gmail.com> wrote:

> Hello,
>
> I have a function that takes a list as its parameter. The list must always
> have the same length, for example 16. Instead of producing a "Nothing" or
> bottom out when an invalid list is supplied, are there ways to verify this
> at compile time? If not, are there alternative data types that has this
> kind of functionality?
>
> Thanks,
> Kelong
>
>
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