teaching machines

CS 330 Lecture 29 – Functional

April 15, 2015 by Chris Johnson. Filed under cs330, lectures, spring 2015.

Agenda

• what ?s
• what makes a language functional
• Haskell
  • expressions
  • functions
  • lists
  • pattern matching
  • partial function application

TODO

• Start the Funfun homework. Due before May 1.
• Pull down to get revised Funfun spec and fix in Timbre grader. See Piazza @16.
• No class on Friday.
• 1/4 sheet: Read first four chapters of Learn You a Haskell for a Great Good.

Code

Hello.hs

import Data.Char

a = 7
-- a = 0 

-- initials :: [Char] -> [Char] -> [Char] -> [Char] 
initials fname mname lname = head fname : head mname : head lname : []

capitalize :: [Char] -> [Char]
capitalize s =
  if s == [] then
    []
  else 
    toUpper (head s) : capitalize (tail s)

capitalize2 s
  | s == [] = []
  | otherwise = toUpper (head s) : capitalize2 (tail s)

capitalize3 s
  case s of
    [] -> []
    (first:rest) -> toUpper first : capitalize2 rest

Haiku