How Append Function Struct

Getting Help Code Review
1

Hello, I have a function that has the structure .signature that adds signatures to a transfer, if I have 1 signature I use it only once, with I have three, as the example below, I use it three times:
signatures := transfer.signature(a[0], b[0]).signature(a[1], b[1]).signature(a[2], b[2])

I would like to create a something like:

var n int
for {

signatures := transfer.signature(a[n], b[n]). //after every loop append one more signature

n++
      if n == number_of_signatures{
          break
      }
}

Aiming to avoid write a different signatures for every different amount of signatures. Anyone could help me?

2 
var signatures XXXX
for i:=0;i<number_of_signatures;i++ {
  signatures += transfer.signature(a[i], b[i])
}

OR

signatures := transfer.sign(a, b)

func (t *transfer) sign(a,b) XXXX{
  var signature XXXX
  for i := range a {
    signature += t.signature(a[i], b[i])
  }
  return signature
}

?

3

Answer:

Just remove the two dots.

var n int
for {

signatures = transfer.signature(a[n], b[n]). //after every loop append one more signature

n++
      if n == number_of_signatures{
          break
      }
}