Hi David I think you’re right: there is no way to test for the existence of a variable whose value is blank. I’ve added an [is[variable]] subfilter operator for v5.1.20 to address this:
https://github.com/Jermolene/TiddlyWiki5/commit/36e76429b1a1d4638374d513430393db5693b932 Best wishes Jeremy. > On 25 Feb 2019, at 12:34, David Nebauer <[email protected]> wrote: > > As I understand it, if you attempt to call an undefined macro the call fails > silently, with nothing displaying in the tiddler to alert users. This occurs > regardless of the calling method, i.e., > > <<not-a-real-macro>> > or > <$macrocall $name="not-a-real-macro"/> > > Is there a technique for checking whether a macro is defined, and displaying > a message in the tiddler if the macro is not defined? > > Ideally, the test would not just check for output from the macro, since there > might be valid circumstances where a macro produces no output. > > -David > > -- > 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] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/tiddlywiki > <https://groups.google.com/group/tiddlywiki>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/tiddlywiki/1ecc0c93-5932-41bb-9634-3eca9daf26c1%40googlegroups.com > > <https://groups.google.com/d/msgid/tiddlywiki/1ecc0c93-5932-41bb-9634-3eca9daf26c1%40googlegroups.com?utm_medium=email&utm_source=footer>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/tiddlywiki. To view this discussion on the web visit https://groups.google.com/d/msgid/tiddlywiki/9F594E37-1458-40C8-B4FC-B7DA7D435DCB%40gmail.com. For more options, visit https://groups.google.com/d/optout.
