There are "InputAliases" ⵗxyzⵗ, "InputAutoReplacements" xyzspace, and things we'll call "long form inputs" \[xyz]. It's easy to view and modify the former two replacements with CurrentValue.
Can I add a new long input form \[xyz] which gets substituted with "abc"?
Better yet, can I remove or temporarily disable one or all existing long inputs? The ideal solution disableLongForms would act such that
disableLongForms[]
Characters@ToString@FullForm@"\[PartialD]" ===\
Join @@ Characters /@ {"\"\[PartialD", "]\""} (*should be False*)
\[xyz]is what is stored in the notebook (in cell boxes) and is parsed when a notebook is opened. I doubt very much this could be disabled. As for extending it, maybe someone will have a way, other than auto replacements. – Michael E2 Jul 04 '23 at 19:12ζwhich isn't expanded to\[Zeta]in a notebook? I tried inserting it in an external editor and got an error loading the nb. – Adam Jul 05 '23 at 00:31