Function Block binding in Haskell

Block binding in Haskell refers to defining a variable using the let keyword within a block of code. This variable is only valid within that block and cannot be accessed outside of it.

Here is an example of using block binding in Haskell:

-- Define a function that calculates the circumference of a circle
circumference :: Float -> Float
circumference r = let piVal = 3.14159 -- define piVal within the block
                  in 2 * piVal * r     -- use piVal to calculate circumference

Here, we define the variable piVal using the let keyword within the block of code following the function definition. We then use this variable to calculate the circumference of a circle.

Another example is:

-- Define a function that takes a list of integers and returns their sum
sumList :: [Int] -> Int
sumList lst = let sumVal = sum lst -- define sumVal within the block
              in sumVal           -- return sumVal

Here, we define the variable sumVal using the let keyword within the block of code following the function definition. We then use this variable to calculate the sum of a list of integers.

Block binding is a useful tool in Haskell for defining variables within specific scopes and can make code more readable and maintainable.