Yes, thanks, I use the toolbar, but I'm referring to a text shorthand, like ~~~~ in MediaWiki.
In some situations, it's more convenient for some to not use the toolbar, as when using on a phone.
All I've found is this
https://www.dokuwiki.org/plugin:wikisign plugin, which promises to do exactly what I'm referring to, but was last updated in 2008, and seemed to be broken even then.