I am trying to write a FizzBuzz program with CoffeeScript like this:
array = [1..100]
console.log(array.forEach(
(value)->
if value%3 is 0 and value%5 is 0
return "fizzbuz"
if value%3 is 0
return "fizz"
if value%5 is 0
return "buzz"
value
))
And it keeps returning undefined. Why does this happen?
Since you're using CoffeeScript, simple for loops are expressions that result in arrays so you could say:
console.log(for value in array
if value % 3 is 0 and value % 5 is 0
"fizzbuz"
else if value % 3 is 0
"fizz"
else if value % 5 is 0
"buzz"
else
value
)
or if you really wanted to use a function, use do to create an SIF:
console.log(for value in array
do (value) ->
return 'fizzbuz' if value % 3 is 0 and value % 5 is 0
return 'fizz' if value % 3 is 0
return 'buzz' if value % 5 is 0
return value
)
The forEach array method doesn't return a resulting array. It executes a function once for each array element, and it doesn't return anything. If you want to return a resulting array, use map.
console.log(array.map(
(value)->
if value%3 is 0 and value%5 is 0
return "fizzbuzz"
if value%3 is 0
return "fizz"
if value%5 is 0
return "buzz"
value
))