Template:If/doc

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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 affect the outcome of the condition.

Usage

• {{if||x| p | q }} gives " p ". Notice the pair of vertical bars surrounding the empty first parameter.
• {{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.

See also

• m:Template:If