RefString.len

Description:

public RefString.len (string str, ssize_t len)

Creates a new reference counted string and copies the contents of str into it, up to len bytes.

Since this function does not stop at nul bytes, it is the caller's responsibility to ensure that str has at least len addressable bytes.

str	a string
len	length of `str` to use, or -1 if `str` is nul-terminated

the newly created reference counted string