joinToString
fun <E : Any> EntitySequence<E, *>.joinToString(separator: CharSequence = ", ", prefix: CharSequence = "", postfix: CharSequence = "", limit: Int = -1, truncated: CharSequence = "...", transform: (E) -> CharSequence? = null): String(source)
Create a string from all the elements separated using separator and using the given prefix and postfix.
If the collection could be huge, you can specify a non-negative value of limit, in which case only the first limit elements will be appended, followed by the truncated string (which defaults to "...").
The operation is terminal.
