Expanding MVV compatibility: a feature wishlist

Developers
1

In a similar vein to V5.4.0 prerelease - Clearifications about MVVs using with various operators… I thought I’d start a new conversation for post-5.4.0 possibilities.

As an avid user of +[format:titlelist[]join[ ]] + enlist<var> constructions, I’ve been excited about the potential of multi-valued variables since they were first teased, and this week I’ve finally found some time to start converting a lot of my old functions, filters, and $let assignments to use the new syntax. This has enabled me to convert a lot of code like this…

\function concepts() [tag[Concepts]] +[format:titlelist[]join[ ]]

<$let variables={{{ [tag[Variables]] +[format:titlelist[]join[ ]] }}}>

{{{ [enlist<concepts>] [enlist<variables>] }}}

into the following simpler alternatives:

\function concepts() [tag[Concepts]]

<$let variables={{{ [tag[Variables]] }}}>

{{{ [(concepts)] [(variables)] }}}

Which is great! Except that I keep running into instances like this…

<$let variables={{{ [tag[Variables]] +[format:titlelist[]join[ ]] }}}>

{{{ [[A]match[A]then<variables>enlist-input[]] }}}

At present, the only filter operators that accept MVVs as parameters (as per the documentation) are title and function. This means that in a scenario like the one above, I can’t actually redefine <<variables>> as an MVV, because I can’t replace <variables>enlist-input[] with (variables). then doesn’t support MVVs, so then(variables) will return only the first title in the list, not the entire list I need.

In this very simplified example, I can replace then with :then as a workaround:

<$let variables={{{ [tag[Variables]] }}}>

{{{ [[A]match[A]] :then[(variables)] }}}

But this isn’t always a viable solution, especially in more complex multi-run filters.

This leads me to a question for our devs: Is it possible to extend additional filter operators to accommodate MVV parameters?

And a discussion question for other users: Which other filter operators would you like to use with MVVs?

My personal wishlist:

  • then, as discussed above
  • other operators that can take space-separated lists, like fields:exclude/fields:include or search::words (where each value in the MVV would constitute a “word” — I expanded on this in a later post)
  • sortby could take a MVV in place of a title list
  • perhaps contains could be similarly extended so that contains:tags(var) would return tiddlers containing all the MVV values in their tag field?
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Announcing the release of TiddlyWiki v5.4.0
2

I am just wondering if MVV’s different values are better described as “titles” rather than “words” however I have not being able to explore the true nature of MVV’s yet to properly understand them deeply. How are they internally delimited?

3

Yes, probably! And generally speaking I’d tend to opt for “strings” rather than “titles”, which might imply that values correspond to extant tiddlers — though obviously this isn’t really true in filter logic, and doesn’t completely describe the way we use constructions like {{!!title}}.

In this case, I used “words” in scare quotes because I was thinking about search::words (i.e. the default form of search) in particular. With the current filter syntax, we can do something like this:

{{{ [search:title[filter operator]] }}}

or

<$let terms="filter operator">

{{{ [search:title<terms>] }}}

The default words mode treats its parameter as a space-separated list of tokens which must all be present in each result, so both of these examples will find tiddlers whose titles contain both “filter” and “operator” — but not necessarily in that order.

I’m imagining an expanded version of search which could accept a MVV in place of a standard variable, something like this:

<$let terms={{{ [[filter operator]] variable }}}>

((terms))

{{{ [search:text(terms)] }}} = {{{ [search:text:literal[filter operator]search:text[variable]] }}}

I’d expect this to return all tiddlers that contained the strings “filter operator” and “variable”. This would allow us to search for multiple tokens which could themselves include whitespace.

1 Like
4

Today’s wishlist items:

  • either a getvariable suffix like getvariable:mvv or a separate operator getmvv. In either case, I’d expect the new form to output the full list of titles defined by the MVV, e.g.
\function test() [tag[HelloThere]]

{{{ [[test]getvariable[]] }}} --> A Gentle Guide to Tiddlywiki

{{{ [[test]getvariable:mvv[]] }}} --> A Gentle Guide to TiddlyWiki Discover TiddlyWiki Some of the things you can do with TiddlyWiki Ten reasons to switch to TiddlyWiki What happened to the original TiddlyWiki? Donations Funding TiddlyWiki Open Collective
1 Like
5

I imagine this is an unlikely dream as the conditional shortcut syntax automatically applies limit="1" to the underlying $list widget… but it’d be really cool if it also assigned a MVV ((condition)) containing the full list of output values. I’m imagining something like this:

<% if [tag[HelloThere]] %>

<<condition>> --> A Gentle Guide to Tiddlywiki

NOT CURRENTLY FUNCTIONAL:
((condition)) --> A Gentle Guide to TiddlyWiki, Discover TiddlyWiki, Some of the things you can do with TiddlyWiki, Ten reasons to switch to TiddlyWiki, What happened to the original TiddlyWiki?, Donations, Funding TiddlyWiki, Open Collective

<% endif %>

This would enable us to use the full set of titles in the conditional’s content a bit more conveniently than the current workaround, which still requires format:titlelist[]join[ ]:

<% if [tag[HelloThere]] +[format:titlelist[]join[ ]] %>

{{{ [enlist<condition>]first[]] }}}  --> A Gentle Guide to Tiddlywiki

{{{ [enlist<condition>] }}} --> A Gentle Guide to TiddlyWiki Discover TiddlyWiki Some of the things you can do with TiddlyWiki Ten reasons to switch to TiddlyWiki What happened to the original TiddlyWiki? Donations Funding TiddlyWiki Open Collective

<% endif %>