On Wed, Nov 17, 2010 at 9:35 PM, John Smith wrote:

My program needs a list such as [IO 3, IO "f", IO 'z'] :: Show s => [IO s]. Is there any way to achieve this without wrapping all the values in existentially quantified types?

Short answer: no. Slightly longer answer: you could just apply "show" to each element in the list and get a list of Strings. Michael