I can't remember how to use "and" and "or" in a filter

#1

The question is stupid, I should know the answer, but I’m not getting it.
How can I, given two conditions, create filters that do “and” and “or”?

For example, these are the two conditions:

[<currentTiddler>get[Field1]count[]match[0]]
[<currentTiddler>get[Field2]count[]match[0]]

How can I combine them to get these two filters?

both fields are empty (1 and 2)
at least one field is empty (1 or 2)

#2

One way to get and is to string together multiple filter operators inside the same filter run. One way to get or is the use two separate filter runs.

* ''both fields'' (and)
** <$text text={{{[<currentTiddler>!has[created]!has[modified]]}}}/>
** <$text text={{{[<currentTiddler>!has[doesnotexist1]!has[modified]]}}}/>
** <$text text={{{[<currentTiddler>!has[created]!has[doesnotexist]]}}}/>
** <$text text={{{[<currentTiddler>!has[doesnotexist1]!has[doesnotexist2]]}}}/>
* ''either field'' (or)
** <$text text={{{[<currentTiddler>!has[created]] [<currentTiddler>!has[modified]]}}}/>
** <$text text={{{[<currentTiddler>!has[doesnotexist1]] [<currentTiddler>!has[modified]]}}}/>
** <$text text={{{[<currentTiddler>!has[created]] [<currentTiddler>!has[doesnotexist]]}}}/>
** <$text text={{{[<currentTiddler>!has[doesnotexist1]] [<currentTiddler>!has[doesnotexist2]]}}}/>

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#3

Thank you!
…unfortunately, sorry :sweat_smile:, I can’t figure out how I should go about creating an “and” filter using the filters I indicated.
Doing it like so doesn’t work (probably beacuse the “get” operator wants a tiddler before it)

[<currentTiddler>get[Field1]count[]match[0]get[Field2]count[]match[0]]

So I tried it like this:

[<currentTiddler>get[Field1]count[]match[0]<currentTiddler>get[Field2]count[]match[0]]

But like this is not “if both fields count = 0” like I’d want, but only “if Field2 count=0”.
Any ideas on how to do it?

2 Likes
#4

Try this:

[<currentTiddler>get[Field1]] [<currentTiddler>get[Field2]] +[count[]match[0]]
1 Like
#5

I wasn’t clear in my response that I replaced your get[field]count[]match[0] with !has[field]

This will output the tiddler name if it has neither field:

[<currentTiddler>!has[Field1]!has[Field2]]

This will output the tiddler name if either of the two fields is missing:

[<currentTiddler>!has[Field1]] [<currentTiddler>!has[Field2]]
1 Like
#6

Just out of curiosity, if I had to do the opposite, what should I do?
( instead of match[0] → !match[0] )

I don’t understand why, but simply adding “!” to the “match” operator

[<currentTiddler>get[Field1]] [<currentTiddler>get[Field2]] +[count[]!match[0]]

doesn’t seem to work

But
I actually looked more closely at the documentation of the “has” operator and the best solution for both cases is to use that operator. I was wrongly convinced that an existing but empty field could create problems.

So really no problem.
(Thanks again to both of you! :grinning_face_with_smiling_eyes:)

#7

In similar cases, rather than !match[0] I have instead used the compare:number:gt[0]] or compare:number:ne[0]]

1 Like