Question

Haskell question, please give an explanation as well.

QUESTION 1 Consider the algebraic type definition: data Foo Bar | Baz Int and the function definition frob Foo->Foo ->Bool frob (Baz j) (Baz k)k frob-False which one of the following is the most concise deriving clause that must be added to the definition of Foo so that the function frob compiles correctly and does the expected computation? deriving (Show, Eq, Ord) deriving Eq deriving (Show, Eq) deriving (Show, Ord) No deriving clause is needed.

Answer 1

algebraic type definition:

data Foo = Bar | Baz int

The above definition of data  of type integer.

function definition:

frob::Foo->Foo ->Bool

frob(Baz j)(Baz k)=j==k

frob__=False

• Here the type of data is Int type is an instance and check the equality so use Eq.
• Eq is mainly used for the == functions with values of that type here the values corresponding to the int.

deriving Eq

Option b