hi, I am a beginner of hugs 98 and I now need to let one function be strictly evaluated in hugs98. In Richard Bird's Introduction to Functional Programming using Haskell Second edition , P 240, it says we can use strict to make it like the following: Let succ x = x + 1 and strict succ (strict succ ( 8 * 5)) will evaluate the expression strictly . But I find the hugs98 do not support it. It even do not recognize strict and in Fethi Rabhi's Algorithms A functional Programming Approach , it use &! operator to inform hugs that the function need be evalutae stricly. This time the hugs recognize it, but I find the cells need for two version do not have much difference Can you tell me how to do it? Thanks very much __________________________________ Do you Yahoo!? New Yahoo! Photos - easier uploading and sharing. http://photos.yahoo.com/