Issues summing up array using for loop in swift -

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i'm trying iterate through array , sum values using generics so:

func reducedaarray <t, u>(a: [t], startingvalue: u, summed: (u, t) -> u) -> u {      var sum = 0      number in {         sum = sum + number     }      return sum }  reducedaarray([2,3,4,5,6], 2, +) //(22)

it's giving me following errors:

binary operator '+' cannot applied operands of type 'int' , 'a' regards line sum = sum + number

and

int not convertible 'u' regards line return sum

i know accomplished better reduce method, wanted complete task using iteration instance practice. why these errors occurring? never explicitly stated t int.

in reducedaarray() function,

var sum = 0

declares integer instead of using given startingvalue. , 

sum = sum + number

tries add generic array element integer, instead of using given summed closure.

so meant is

func reducedaarray <t, u>(a: [t], startingvalue: u, summed: (u, t) -> u) -> u {      var sum = startingvalue     number in {         sum = summed(sum, number)     }     return sum }

which compiles , works expected:

let x = reducedaarray([2, 3, 4, 5, 6], 2, +) println(x) // 22 let y = reducedaarray([1.1, 2.2], 3.3, *) println(y) // 7.986 let z = reducedaarray(["bar", "baz"], "foo") { $0 + "-" + $1 } println(z) // foo-bar-baz

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