I don't understand your question but the class Ord in Data.Ord is our tool for comparisons. You may want to look into that. You can also use the function "on" from Data.Function to compare on a specific record within a larger structure. Dimitri On 11/24/15 11:20 AM, Jeon-Young Kang wrote:
Dear All.
I'd like to compare fields of each record.
here is my record.
data Person = Person {name:: String, age:: Int } deriving(Show) data Relations = Friend | Older | Younger
class Comparison a where compare:: a -> a -> Relations
instance Comparison Person where compare Person a b Person a b | b1 == b2 = Friend | b1 > b2 = Older | b1 < b2 = Younger
How can I fit it?
Sincerely,
Jeon-Young Kang
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