{{#invoke:Message box|mbox}} With this template the parser functions of the ParserFunctions collection with names starting with "#if" can be used in a way such that they do not strip spaces and newlines from the "then" and "else" part. Spaces still do not affext the outcome of the condition.
Usage
- {{if||x| p | q }} gives " p "
- {{if|expr|2<3| p | q }} gives " p "
- {{if|eq| u |u| p | q }} gives " p "
- {{if|exist| Help:Link | p | q }} gives " q "
- {{if|error|{{#expr:x}}| p | q }} gives " p "
Compare:
- {{#if:x| p | q }} gives "p"
- {{#ifexpr:2<3| p | q }} gives "p"
- {{#ifeq: u |u| p | q }} gives "p"
- {{#ifexist: Help:Link | p | q }} gives "q"
- {{#iferror:{{#expr:x}}| p | q }} gives "p"
For full substitution, use e.g. {{subst:if|expr|2<3| p | q |subst=subst:}}. If the condition contains a parser function or template etc., that should be substituted too. Optionally the "then" or "else" part can also be substituted.