Template:Qif/doc

Template:Qif formerly implemented an "if" function, which is now implemented by the parser function {{#if}}.

Purpose and function

Provides if then else functionality.

• Parameter else is optional.
• This template has undefined behaviour, if parameter test or then (or both) are missing.
• This template also has undefined behaviour, if any parameter (be it named or unnamed) that is different from test, then or else is defined when calling the template.

Note that {{qif}} does not work when subst'ed (like {{ifndef}}, the then part alone as in {{ifdef}} can be substituted).

Of course it's impossible to use vertical bars in parameter values directly, use either | or Template:! – the latter is only relevant for wiki table delimiters.

Wikipedia CTO Brooke Vibber expressed support to implement the functionality of qif into MediaWiki; this became {{#if}}.

Usage

{{Qif
  |test=VARIABLE_OR_PARAMETER_TO_TEST
  |then=code if 'test' is not empty
  |else=code if 'test' is empty
}}

Parameter else is optional. So this was also possible:

{{Qif
  |test=VARIABLE_OR_PARAMETER_TO_TEST
  |then=code if 'test' is not empty
}}

Examples

Code	Result
{{Qif |test={{boolne|foo|bar}} |then=true |else=false }}	true
{{Qif |test={{booleq|foo|bar}} |then=true |else=false }}	false
{{Qif |test= |then=bar }}
{{Qif |test=foo |then=bar }}	bar

See also

• Template:Switch(edit talk links history)
• Template:If (edit · talk · links · history) at Meta explains "undefined" cases
• Template:Ifdef (edit · talk · links · history) at Meta allows substitution
• Category:If-then-else templates
• Help:Conditional tables
• ParserFunctions