This forms located at com.nihirash.ells.lib.StringForms class.
This forms returns string length.
Example:
(string-length "Hello")
This forms creates new string from substring of first argument by skipping second-argument symbols and with third-argument length.
Example:
(substring "-=()=-" 2 2)
This form concatenate all arguments to new string.
Example:
(string-append
"Hello, " "world" "!")
This form splits string(first argument) with using separator(second argument).
Example:
(split-string "1,2,3" ",")