An answer more specific to you case
\define mymacro(var1 var2)
<$set name=result value="$var1$" emptyValue="$var2$">
<<result>>
</$set>
\end
But the above does not address if var2 is empty
Regards
Tony
On Wednesday, July 18, 2018 at 10:36:52 AM UTC+10, TonyM wrote:
>
> Talha,
>
> The default value set in the define macro can distract you from another
> way of setting a default value, using the setWidgets emptyValue or
> listwidgets emptyMessage
>
> In the below example should be sufficient to explain what I mean. Note the
> convenience of having an input fieldname value $fieldname$ and variable
> <<fieldname>>
>
> \define mymacro(fieldname)
> <$set name=fieldname value="$fieldname$" emptyValue="default value">
> <<fieldname>>
> </$set>
> \end
>
>
> <<mymacro>>
> <<mymacro description>>
>
> Then if the macro is calling other macros or widgets use the $macrocall
> widget then you can pass <<fieldname>> into those macros
>
> Eg; In the above macro
>
> <$macrocall $name="othermacroorwidget" inputvalue=<<fieldname>>/>
>
>
> or outside the macro in wikitext
>
>
> <$macrocall $name="mymacro" fieldname="description"/>
> <$macrocall $name="mymacro" fieldname=<<othermacro>>/>
>
>
> <$macrocall $name="mymacro" fieldname={{!!description}}/>
>
>
> Note: field transclusion example Not tested today
>
>
> The above is not using the <<__fieldname__>> method I am yet to digest. It
> may reduce the need for $macrocall however this is a nice method to use
> especially in macros
>
> Macros that you design for re-use, they spell it out and don't rely on the
> position of values you pass to the macro you are calling.
>
>
> Additional advanced note:
>
> If you use recursion where mymacro calls itself mymacro such as in toc
> macros, it is a fact that the fieldname $fieldname$ and variable
> <<fieldname>> will be reused for each invocation thus they have the same name
> but will not have the same value.
>
> So if the recursion went 5 levels deep each invocation will use an
> independent set of variables called fieldname for each level
>
>
> Regards
>
> Tony
>
>
> On Wednesday, July 18, 2018 at 3:05:46 AM UTC+10, talha131 wrote:
>>
>> Say I have a macro
>>
>> \define example(v1, v2:"")
>> \end
>>
>> If v2 is empty than I want to assign value of v1 to v2. What’s the TW
>> syntax for this?
>>
>>
>
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