{- 

Improved text editing for input
CSE 341

The standard getLine action doesn't handle backspace, control-w, and
so forth when you are running with ghci; but it does when you use
runhaskell or compile the program.

If you really want editing to work when you are using ghci, here is an
alternative action, getInputLine, from System.Console.Haskeline

This is the same print_one_trig_fact program as in BasicInputOutput.

-}

module BetterInput
    where

import System.Console.Haskeline
import Data.Maybe

{- return a string consisting of a number and its sin and cos -}
trig_facts :: Float -> String
trig_facts x = "x=" ++ show x ++ " sin(x)=" ++ show (sin x) 
               ++ " cos(x)=" ++ show(cos x)

{- prompt for one number and print the trig_facts for it -}
print_one_trig_fact = do
  m <- runInputT defaultSettings (getInputLine "Please enter a number: ")
  let x = read (fromJust m)
  putStrLn (trig_facts x)