These are planned to be removed in 2021.10. Please update
your sources to use the newer names.

~~~
:s:split (sc-ss) s:split/char ;
:s:split-on-string (ss-ss) s:split/string ;
:s:contains-char? s:contains/char? ;
:s:contains-string? s:contains/string? ;
:a:contains-string? a:contains/string? ;

:a:index-of a:index ;
:a:index-of-string a:index/string ;
:s:index-of s:index/char ;
:s:index-of-string s:index/string ;
~~~