concatstring.go

func concatstrings(a []string) string {
    idx := 0
    l := 0
    count := 0
    for i, x := range a {
        n := len(x)
            if n == 0 {
            continue
        }
        if l+n < l {
            gothrow("string concatenation too long")
        }
        l += n
        count++
        idx = i
    }
    if count == 0 {
        return ""
    }
    if count == 1 {
        return a[idx]
    }
    s, b := rawstring(l)
    l = 0
    for _, x := range a {
        copy(b[l:], x)
        l += len(x)
    }
    return s
}