String Module
import split, join, upper, lower, trim from string
Common functions: split, join, upper, lower, trim, contains, replace
Also: trim_start, trim_end, starts_with, ends_with, index_of_str, replace_all, slice_str, char_at, repeat, pad_start, pad_end
Strings support direct indexing:
"hello"[0] // "h"
"hello"[4] // "o"