Simple check: if a tiddler-A exists do this if not then do that

[Mohammad]

This is may be repetitive question!

I need a macro to conditionally does the following tasks

If tiddler-A exist

  navigate to it

else

  create tiddler-A

  put some text inside it and tag it with myTag

  navigate to it

end if

 I thought it may be possible using some list widgets

Mohammad

[Mark S.]

You can create a tiddler name in a filter, and then check if it has an actual title field.

\define nontidexist(tiddler)
$tiddler$ does not EXIST!
\end
\define tidexist(tiddler)
<$vars tiddler="""$tiddler$""">
<$list filter="[title[$tiddler$]] +[has[title]]" emptyMessage=<<nontidexist """$tiddler$""">>>
$tiddler$ EXISTS. THEREFORE IT WIKIS.
</$list>
</$vars>
\end

You can put in the actions you want for existing tiddlers inside the list widget and the actions you want for creating new tiddlers inside the nontidexist macro.

HTH

-- Mark

[Mohammad]

Wow! 

Thank you Mark!

It works and do the job like a charm!

For action command like create tiddler I call the macro using a button!

Much appreciated!

Mark, one more question is it possible to have a decision making structure like below:

If true-this

 macro-action-if-part

else

  macro-action-else-part

end if

Then the header of macro should be something like 

\define dcm(cond, ifpart-action, elsepart-action)

For checking the condition parameter to see if true or false, the setVars widget from Tobias Beer may be useful! If not we can first check the condition outside the macro and send the result (true/false) to it.

Cheers

Mohammad

[Diego Mesa]

Hey Mohammad,

Just letting you know of Evan's excellent Condition Plugin:

http://evanbalster.com/tiddlywiki/formulas.html#Condition%20Plugin

which does that

[Mohammad]

Hello Diego!
Thanks for the link! It is very close to what I want!

Lets give it a try! 

Best

Mohammad

[Mark S.]

If by "condition" you mean filter, then this works:

\define if(filter,ifyes,ifno)
<$list filter="""$filter$ +[limit[1]]""" name=act emptyMessage=<<$ifno$>>>
<<$ifyes$>>
</$list>
\end
\define ifyes() YES!
\define ifno() NO!


<<if "[title[GettingStarted]] +[has[title]]" ifyes ifno>>

Well, it worked once ;-)  You would probably need to wrap this invocation in another macro in order to  pass the tiddler name as a parameter.

I always prefer core-based solutions if possible over 3rd party solutions, since core-based solutions are more likely to stand the rigors of time.

-- Mark

[Mohammad]

Thank you Mark!

Yes, I prefer the same! the core-based solution!

Let me to play and experiment with what you suggest then I will back with results.

I am not sure if all conditions can be implemented using filter or not!

We may need to ask Jeremy to improve the core capability with more robust and simple to understand routine!

Mohammad

[Mohammad]

Mark one question:

In both solution you proposed you put the filter and tiddler parameters inside triple quotes when you pass them again to another macro or widget!

Whats the reason?

Mohammad

On Friday, August 10, 2018 at 11:45:19 PM UTC+4:30, Mark S. wrote:

[Mark S.]

I could give a sophisticated answer but really it's mostly because it's what I've seen in other people's code. Monkey see -- monkey code.

-- Mark

[TonyM]

Mohammad,

I am not sure if this adds to the conversation but 

a tiddler existence test can be written in a filter as follows

[[other]has:field[text]] where the tiddler is called other and has content in the text field

or any other field you know has a value

[[other]has:field[fieldname]]

Interestingly fields other than text return with or without content as long as they exist, not the text field.

Variations

[[other]value[]] with be true if the value field exists on "other" AND is empty, you could put a value [[other]value[testvalue]]

[[other]text[]]  with be true if the value field exists on "other" AND is empty (if you expect the text to be empty this is a good existence test

Also

The quickest way to create a tiddler is to edit it, but it is manual

<$edit-text class='tc-edit-texteditor' tiddler=other field='value'/>

<$edit-text class='tc-edit-texteditor' tiddler=other field='text'/>

Or this

\define note-tiddler() $(currentTiddler)$/notes

<$edit-text class='tc-edit-texteditor' tiddler=<<note-tiddler>> field='text'/>

Anyway,

I am taking these ideas and experimenting further.

Including a ways to deal with tiddler renames. Not withstanding the value of the comments plugin in 5.1.18

Regards

Tony

[Mohammad]

Thank you both (Mark and Tony!).

I understood that way I can pass complex names and values like myTids/itsname or name'extet 

Mohammad