functional programming - Error with functions inside tuples in Haskell -


i'm playing little haskell , i'm stuck error, using snd function tuple (string, list).

snd ("felix felices",[("escarabajos machacados",52,[f1,f2]),("ojo de tigre sucio",2,[f2])]) error - cannot find "show" function for: *** expression : snd ("felix felices",[("escarabajos machacados",52,[f1,f2]),("ojo de tigre sucio",2,[f2])]) *** of type    : [([char],integer,[(integer,integer,integer) -> (integer,integer,integer)])]

the thing is, if remove f1, f2 , f3 (they functions) code works fine, returns list. why happening, why can't put function inside tuple's second position?

you can put functions tuples. can't display them - ghci wants show result , print it. how should show (convert string) functions? can't, or @ least nobody felt choosing 1 way of doing (which propably flawed anyway - @ least can't think of approach doesn't have holes huge can see them). therefore, can't evaluate returns functions or collections of functions in ghci.


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