MarkupExpressionSamples-Talk
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MX returning part of page text variable name used in conditional
I'm trying to use {(math )} and/or {(calc )} along with PmWiki's PTVs and conditional markup, buts not working as expected. I've tried this on a fresh new wiki install with no other recipes. Here's what I'm doing:
(:X:2:)
(:Y:2:)
(:X4Y4:10:)
(:if equal "{$:X4Y4}" "10":)
EQUAL
(:else:)
NOT EQUAL
(:ifend:)
|
above returns "EQUAL" as expected, but:
(:if equal "{$:X{(math {$:X} + {$:Y})}Y4}" "10":)
EQUAL
(:else:)
NOT EQUAL
(:ifend:)
|
returns "NOT EQUAL". Same with
(:if equal "{$:X{(calc '{$:X} + {$:Y}')}Y4}" "10":)
EQUAL
(:else:)
NOT EQUAL
(:ifend:)
|
This may be related to the order of processing of markup rules, page text variables come before markup expressions which come before conditionals: I suspect at the time the "equal" conditional is evaluated, the first argument is the text string "{$:X4Y4}" and not (yet) "10" which may be re-evaluated at a later point.
If you need complex calculations, it may be easier to write a custom conditional that is processed separately, see ConditionalMarkupSamples for examples; or a custom markup rule that outputs something based on other variables in the current page, see MarkupDirectiveFunctions for a quick start and Functions for PageTextVar(). --Petko
Talk page for the MarkupExpressionSamples recipe (users?).