Just some coding fun: an IF macro for If-Then-Else functionality

1

(Apologies if this is a repeat of something already shared)

For whatever reason, I had this itch I needed to scratch: how would I go about setting up a macro that would result in a given “then” wikitext if a condition is true, and a given “else” wikitext if a condition is false.

The macro:

\define IF( condition then else )
  <$list filter="""$condition$""">
    $then$
  </$list>
  <$list filter="""$condition$ +[else[no value from condition]] +[match[no value from condition]]""">
    $else$
  </$list>
\end

A sample macro reference:

<<IF """[<now “dddd”>match[7]]"""
     """Today is Sunday"""
     """Today is not Sunday""">>
4 Likes
2

Then, if for some reason we have a large number of places where we check to see if today is Sunday, we might like to do this:

Macros:

\define IF( condition then else )
 <$list filter="""$condition$""">
    $then$
 </$list>
 <$list filter="""$condition$ +[else[no value from condition]] +[match[no value from condition]]""">
    $else$
 </$list>
\end

\define ifSunday( then else )
  <<IF """[<now "dddd">match[7]]"""
       """$then$"""
       """$else$""">>
\end

<<ifSunday  """Today is Sunday"""
            """Today is not Sunday""">>
3

And then, if you’re an old-timer like me who likes “keywords”:

\define IF( condition kw1 then kw2 else )
  <$list filter="""$condition$""">
    $then$
  </$list>
  <$list filter="""$condition$ +[else[no value from condition]] +[match[no value from condition]]""">
    $else$
  </$list>
\end

<<IF """[<now “dddd”>match[7]]"""
     THEN  """Today is Sunday"""
     ELSE  """Today is not Sunday""">>
4

That looks a lot like: https://tiddlywiki.com/#Conditional%20Shortcut%20Syntax

5

Yes, but minus the cognitive nickel and diming via semantic symbols.

Square and squiggly brackets and “<” + “>” I’ve gotten to manage with. “<%” and “%>” drive me up the wall. “<$” and “/>”: not a fan, but there really could not be a better choice.