The (`elem` members) function will tell you if the person is a member of
members. You can then turn that boolean into your custom State type.
On Dec 3, 2015 11:46 PM, "Jeon-Young Kang"
Hi all.
I'd like to apply lookup function (Data.Map) for what I am working on.
Here is my code.
data Person = Person {personId :: Int, name = String} data People = [Person]
data State = InMembership | NoMemebership
person1 = Person {1 = personId, "James" = name} person2 = Person {2 = personId, "Tom" = name}
members = People [person1, person2]
class Belonging a where belonging :: a -> [a] -> Bool -> State
here is the problem... I don't know how to get to know whether a person is belong to members. I'd like to find it through a person's name.
Can you suggest any examples??
Sincerely, Jeon
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