Possible autocomplete-related grammar error? ^_^
I'm not a user of Apple products, but in the Linux world there are code editors that enable the user to define custom completions. I find this to be an excellent productivity feature, not just for coding.
The editor Geany calls them snippets.
For autocorrect I'm talking about corrections that are less predictable such as spelling or grammar errors. They can be very useful because they mean fixes happen without any extra work, and mean you don't see lots of red spelling errors in your document... but it's also a case where computer is doing automatic work that sometimes might be wrong. So needs good way to indicate that correction has happened and easy way to revert.