[Feature Request] create a "getkeyvalues" operator which creates a "key" and a "value" internal variable

[pmario]

Describe the bug

See discussion at: https://talk.tiddlywiki.org/t/inverse-index-how-do-i-find-the-indexes-whose-value-contain-a-specific-word/10697/7?u=pmario

Expected behavior

It was rejected, so I made a plugin. But that was before we had Named Filter Run Prefix

Since there is the demand to "store" some intermediate "results" into variables other than currentTiddler, it may be possible store currentTiddler = key and value into intermediate variables.

So filters may be able to look like this:

[[test]getkeyvalues[]] :map[<key>addsuffix[ : ]addsuffix<value>]

This would eliminate all the complex parameters that I had to define for my keyvalues-plugin.

I'm not sure if something as follows would be possible to implement. But it should be -- (just brainstorming)

[[test]getkeyvalues[]] :filter[<key>prefix[test-]] :map[<key>addsuffix[ : ]addsuffix<value>]

I'll add this to my issues-list for the plugin, so I do not forget about it.