That is a distinction in the operators which had completely eluded me. That was extremely helpful, thank you!
On Friday, November 1, 2019 at 7:22:26 AM UTC-4, Eric Shulman wrote: > > On Friday, November 1, 2019 at 4:06:22 AM UTC-7, Andrés Pérez wrote: >> >> So this is probably me not understanding something fully, so I am asking >> here to be better educated. I was playing around with a viewtemplate and >> thought about how to apply it based on tiddler title. When I did that >> filter, though, it applied the template to every single tiddler. >> >> So I have these two viewtemplate-tagged tiddlers: >> Title-based: >> >>> <$list filter="[all[current]is[tiddler]!is[system]title[foobar]]"> >>> foo >>> </$list> >> >> >> Tag-based: >> >>> <$list filter="[all[current]is[tiddler]!is[system]tag[foobar]]"> >>> bar >>> </$list> >> >> >> My expectation is that the title-based viewtemplate only gets applied to >> a tiddler with a title of 'foobar' and the tag-based one is only applied to >> tiddlers with a tag of "foobar'. >> What winds up happening is that the tag-based template only gets applied >> based on the tag, but the title-based one gets applied to all tiddlers. >> >> I feel like this is due to something fundamental/important in how this is >> all put together, but I don't know what or why. >> >> I have a working example in this link: >> >> https://storage.googleapis.com/hgdrop/titlebasedtemplate.html#TagBasedViewTemplate:foobar%20blankTiddler%20tagged%20TitleBasedViewTemplate%20TagBasedViewTemplate >> >> >> And a wordier description here: >> >> With the two ViewTemplates described above, and these 3 tiddlers with no >> contents: >> A: Title: foobar, Tag: *none* >> B: Title: blankTiddler, Tag: *none* >> C: Title: tagged, Tag: foobar >> >> My expectation is that the contents of the three tiddlers be: >> A: foo >> B: *nothing* >> C: bar >> >> Actual rendered contents: >> A: foo >> B: foo >> C: foo bar >> > > The following note appears in the documentation for > https://tiddlywiki.com/#title%20Operator > > title is a constructor (except in the form !title), but field:title is a >> modifier. > > > see https://tiddlywiki.com/#Selection%20Constructors, which explains: > > The output of a Filter Step depends on its operator: >> Most operators derive their output from their input. For example, many of >> them output a subset of their input, and thus truly live up to the name of >> "filters", narrowing down the overall output of the containing run. These >> operators are called selection modifiers. >> A few operators ignore their input and generate an independent output >> instead. These are called selection constructors: they construct an >> entirely new selection. >> A good example of a constructor is title. The output of >> [title[A]title[B]] is just B. But the field operator is a modifier, so >> [title[A]field:title[B] outputs nothing at all. > > > Thus, in your experiment: > "title[foobar]" is a "constructor" that always returns "foobar" regardless > of what precedes it in the filter, while "field:title[foobar]" is a > "modifier" that only returns "foobar" if the preceding filter terms already > contain "foobar" > > enjoy, > -e > Eric Shulman > TiddlyTools: "Small Tools for Big Ideas!" (tm) > http://tiddlytools.github.io/ > InsideTiddlyWiki: The Missing Manuals > http://insidetiddlywiki.tiddlyspot.com/ > > -- You received this message because you are subscribed to the Google Groups "TiddlyWiki" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/tiddlywiki/c5a1ed53-b95b-4578-9e6d-83caa53f060c%40googlegroups.com.
