hi , 

I am stuck in the following problem. 

I am maintaining  a list of  tuples of the form 

([Char],Int,Int, Int,Int) . The purpose of maintaining the tuples is that the 

program reads from a file line by line , Matches the contents with the first element of the tuple and updates the tuple respectively.

The precise function I am using is as follows 

tupup::Bool->[Char]->Int->Int->Int->Int->Char->([Char],Int,Int,Int,Int) 

tupup val elf els elr ell elx ys= if val then 

                                          case ys of  'A'  -> (elf, els+1,elr,ell,elx) 

                                                      'G'  -> (elf,els, elr +1,ell,elx)

                                                      'C'  -> (elf,els,elr,  ell +1,elx) 

                                                      'T'  -> (elf,els,elr,ell,  elx +1)

                                           else (elf,els,elr,ell,elx)

uptable::[[Char]]->[([Char],Int,Int,Int,Int)]->[([Char],Int,Int,Int,Int)]

uptable (xf:xs) main_array = map (\(x,y,z,r,t)-> tupup (x==xf) x y z r t (secvalue xs) ) main_array

   

 

It gives the error ERROR - Control stack overflow. I assume it is because of the lazy evaluation . 

Is there a way to enforce strict evaluation only for the function tupup. 

Thanks, 

Navin