Help:Templates/nqo

ߣߌ߫ ߛߓߍߟߌ߫ ߞߟߊ߬ߟߊ߬ߡߊ ߘߏ߫ ߦߵߌ ߓߟߏ߫ ߌ ߦߋ߫ ߡߍ߲ ߠߊߘߏ߲߬ ߞߏ ߘߐ߫ ߞߐߜߍ߫ ߛߌߦߊߡߊ߲߫ ߠߎ߫ ߟߊ߫߸ ߡߋߘߌߦߊߥߞߌ ߞߙߊߞߏ ߟߊߓߊ߯ߙߊ ߘߌ߫ ߣߊ߬ ߞߍߟߌ߫ ߞߊ߲ߡߊ߬. ߘߐ߬ߥߙߊ߬ߟߌ ߣߌ߫ ߟߊߛߋߢߊߥߙߍ ߞߐߕߐ߮ ߟߎ߬ ߛߋ߲߬ ߕߴߊ߬ ߘߐ߫߸ ߓߊߏ߬ ߡߊ߬ߞߍ߬ߦߙߐ ߕߊ߲ߓߊ߲ ߕߍ߫ ߞߙߊߞߏ ߦߋ߫. ߞߙߊߞߏ ߟߎ߬ ߦߋ߫ ߞߍ߫ ߟߊ߫ ߛߓߍߣߍ߲߫ ߞߎߘߊ ߟߋ߬ ߘߌ߫ ߥߟߴߊ߬ ߟߊߞߎ߲߬ߘߎ߬ߣߍ߲߬ ߦߋ߫ ߞߍ߫ ߓߊߟߌߟߌ ߓߊ߯ߙߊ߫ ߞߍߣߍ߲߫ ߞߘߐ ߘߊߞߘߐ߫߸ ߡߍ߲ ߟߊߝߏ߬ߦߌ߬ߣߍ߲߬ ߦߋ߫ ߞߊ߬ ߝߘߊ߫ ߥߞߌ߫ ߜߘߍ߫ ߟߊ߫ ߟߊߒߡߊ߫ ߘߐ߫ ߥߞߌߔߋߘߌߦߊ߸ ߊ߬ ߣߌ߫ ߞߵߊ߬ ߟߊߛߣߍ߫ ߕߊ߯ߦߙߐ߫ ߥߞߌ ߘߐ߫.

ߛߌ߲ߘߟߌ
ߞߙߊߞߏ ߟߎ߬ ߦߋ߫ ߥߞߌ ߞߐߜߍ߫ ߞߟߊ߬ߟߊ߬ߡߊ ߟߋ߬ ߘߌ߫ ߡߍ߲ ߠߎ߬ ߞߣߐߘߐ ߟߎ߬ ߘߐߓߍ߲߬ߣߍ߲߬ ߦߴߊ߬ ߟߊ߫ ߴߴߥߊ߬ߟߊ߲߬ߞߌ߬ߴߴ (ߟߊߘߏ߲߬ ߠߊ߫) ߞߊ߲ߡߊ߬ ߞߐߜߍ ߕߐ߭ ߟߎ߬ ߟߊ߫. ߞߙߊߞߏ (ߕߊ߲ߔߑߟߋߕ) ߦߋ߫ ߓߍ߲߬ߡߊ߬ߞߊ߲ ߠߋ߬ ߟߊߓߊ߬ߕߏ߬ ߟߊ߫ ߡߍ߲ ߕߐ߮ ߦߋ߫ ߢߍߣߙߊ ߘߌ߫ ߴߴ ߴߴ ߦߋ߫ ߡߍ߲ ߠߊ߫߸ ߣߴߊ߬ ߦߋ߫ ߘߍ߬ߡߍ߲߬ߘߌ߬ ߟߊ߫ ߕߐ߯ߛߓߍߞߣߍ ߣߌ߲߬ ߠߊ߫: ߣߴߏ߬ ߕߍ߫ ߘߏ߲߬߸ ߌ ߘߌ߫ ߛߋ߫ ߊ߬ߟߎ߬ ߛߌ߲ߘߌ߫ ߟߊ߫ ߦߏ߫ ߥߞߌ߫ ߞߐߜߍ ߕߐ߭ ߟߎ߬.

ߞߙߊߞߏ ߟߊߓߊ߯ߙߊߟߌ ߣߐ߰ߡߊ߲߬ߓߊ ߟߋ߬ ߦߋ߫ ߢߊ ߢߌ߲߬ ߠߎ߬ ߞߊ߲߬. ߣߴߌ ߞߊ߬ ߞߐߜߍ ߘߏ߫ ߛߌ߲ߘߌ߫ ߡߍ߲ ߦߋ߫ ߞߟߌ߫ ߟߊ߫ ߞߏ߫ ߴߴߞߙߊߞߏ:ߌ ߣߌ߫ ߛߣߍ߫ߴߴ ߞߣߐߘߐ ߘߐ߫:

ߌ ߣߌ߫ ߕߎ߬ߡߊ߬߹ ߌ ߣߌ߫ ߛߣߍ߫ ߥߞߌ ߞߊ߲߬.

ߌ ߓߘߴߌ ߟߊ߫ ߞߙߊߞߏ߫ ߝߟߐ ߛߌ߲ߘߌ߫߹ ߏ߬ ߘߐ߫ ߣߴߌ ߞߊ߬ ߘߏߞߊ߲ (ߞߐߘ) ߠߊߘߏ߲߬:

ߞߐߜߍ ߛߎ߯-ߎ-ߛߎ߫ ߘߐ߫߸ ߣߌ߫ ߞߐߜߍ ߏ߬ ߦߌ߬ߘߊ߬ ߘߊ߫ ߛߓߍߟߌ ߴߴߌ ߣߌ߫ ߕߎ߬ߡߊ߬߹ ߌ ߣߌ߫ ߛߣߍ߫ ߥߞߌ ߞߊ߲߬.ߴߴ ߏ߬ ߓߐ߫ ߞߋߟߋ߲ߘߌ߫  ߘߌ߫. ߏ߬ ߓߊ߯ ߞߍ߫ ߞߙߊߞߏ ߞߣߐߘߐ ߟߎ߬ ߘߌ߫ ߴߴߥߊ߬ߟߊ߲߬ߞߌ߫ߴߴ ߞߐߜߍ߫ ߜߘߍ ߏ߬ ߘߐ߫߸ ߊ߬ ߢߊߝߐߟߌ߫ ߜߘߍ߫ ߘߐ߫߸ ߊ߬ ߘߌ߫ ߓߌ߬ߟߊ߬ ߞߐߜߍ ߏ߬ ߟߊ߫.

ߌ ߘߌ߫ ߛߋ߫  ߟߊߘߏ߲߬ ߠߊ߫ ߞߐߜߍ ߛߎ߮ ߓߍ߯ ߦߙߐ ߘߏ߫ ߟߊ߫ ߌ ߦߴߊ߬ ߝߍ߬ ߞߵߊ߬ ߟߊߘߏ߲߬ ߡߍ߲ ߠߊ߫ ߡߐ߱ ߘߏ߫ ߟߊߛߣߍ߫ ߞߊ߲ߡߊ߬. ߡߍ߲ ߞߊߞߊ߲߫ ߞߊ߬ ߟߊߓߊ߯ߙߊ߫ ߞߐߜߍ߫ ߁߀߀ ߟߊ߫. ߣߴߌ ߘߏ߲߬ ߞߊ߬ ߞߙߊߞߏ ߞߣߐߘߐ ߟߎ߬ ߡߊߦߟߍ߬ߡߊ߲߫ ߞߵߊ߬ ߞߍ߫:

ߌ ߣߌ߫ ߕߎ߬ߡߊ߫ ߦߋ߲߬߹ ߌ ߣߌ߫ ߛߣߍ߫ ߥߞߌ߫ ߡߊߞߓߊߣߍ߲ ߞߊ߲߬.

ߌ ߓߊ߯ ߥߊ߫ ߓߐ߫ ߞߐߜߍ߫ ߁߀߀ ߏ߬ ߟߎ߬ ߛߎ߯-ߎ-ߛߎ߫ ߞߊ߲߬߸ ߌ ߣߊ߬ ߞߙߊߞߏ ߟߊߘߏ߲߬ ߠߊ߫ ߡߍ߲ ߠߎ߬ ߟߊ߫߸ ߌ ߘߌ߫ ߥߊ߫ ߛߓߍߟߌ߫ ߞߎߘߊ߫ ߕߍ߬ߘߍ߫ ߦߋ߲߬ ߡߍ߲ ߣߴߌ ߟߊ߫ ߟߊ߬ߘߏ߲߬ߣߍ߲ ߕߍ߫ ߞߋߟߋ߲߫ ߘߌ߫. ߒ߬ߓߊ߬ ߢߊ ߏ߬ ߡߊ߬߸ ߌ ߓߘߊ߫ ߞߐߜߍ߫ ߁߀߀ ߏ߬ ߟߎ߬ ߓߍ߯ ߞߣߐߘߐ ߡߊߦߟߍ߬ߡߊ߲߫ ߠߵߏ߬ ߘߌ߫ ߞߵߊ߬ ߕߘߍ߬ ߌ ߡߴߊ߬ߟߎ߬ ߡߊߦߟߍ߬ߡߊ߲߫߸ ߓߊߏ߬ ߞߙߊߞߏ ߓߘߊ߫ ߟߊߥߊ߬ߟߊ߲߬ߞߌ߫ ߞߐߜߍ ߏ߬ ߟߎ߬ ߟߊ߫.

This is the basic mechanism. There are several additional features of transclusion that enrich this mechanism and make templates very useful.

ߟߊߓߊ߯ߙߊߟߌ
ߞߙߊߞߏ ߘߌ߫ ߛߋ߫ ߟߊߓߊ߯ߙߊ߫ ߟߊ߫ ߞߐߜߍ߫ ߜߘߍ߫ ߟߎ߫ ߟߊ߫ ߛߌߟߊ ߣߌ߲߬ ߝߍ߬:

- ߣߌ߫ ߞߙߊߞߏ ߣߌ߲߬ ߛߘߌ߬ߜߋ߲ ߟߊߓߊ߯ߙߊ߫ ߘߊ߫߸ ߊ߬ ߘߌ߫ ߣߐ߬ߘߐߓߌ߬ߟߊ߫ ߛߋ߲߬ߧߊ߬ ߞߋߟߋ߲߫ ߊ߬ ߣߌ߫ ߞߙߊߞߏ:ߕߐ߮ ߞߣߐߘߐ ߓߍ߯ ߝߣߊ߫ ߟߴߊ߬ ߣߌ߫ ߕߎ߬ߡߊ߬ ߟߊ߫߸ ߣߌ߫ ߛߘߌ߬ߜߋ߲ ߴߴߠߊߞߎ߲߬ߘߎ߬ߵߵ ߘߊ߫: ߞߙߊߞߏ:ߕߐ߮ ߞߣߐߘߐ ߓߊߞߎߘߊ ߘߌ߫ ߣߐ߬ߘߐߓߌ߬ߟߊ߬ ߞߙߊߞߏ ߛߘߌ߬ߜߋ߲ ߠߊ߫. ߏ߬ ߓߊ߯ ߞߍ߫ ߞߣߐߘߐ ߓߘߊ߫ ߞߍ߫ ߞߐߜߍ߫ ߛߋ߲߬ߓߐߣߍ߲ ߘߌ߫߸ ߊ߬ ߣߴߊ߬ ߘߌ߫ ߛߋ߫ ߡߊߦߟߍ߬ߡߊ߲߫ ߠߊ߫ ߢߊߓߘߍ ߡߊ߬߸ ߝߘߊߟߌߓߟߏߡߊ߬ ߞߐߜߍ ߓߐߛߎ߲ ߡߊ߬. ߴߴߞߟߏߜߍߴߴ: ߡߊ߬ߦߟߍ߬ߡߊ߲߬ߠߌ߲߬ ߜߘߍ ߡߍ߲ ߠߎ߬ ߞߍߕߐ߫ ߞߐߝߍ߬ ߞߙߊߞߏ ߓߐߛߎ߲ ߘߐ߫߸ ߏ߬ ߟߎ߬ ߕߍߣߊ߬ ߟߊߖߍ߲ߛߍ߲߫ ߠߊ߫ ߞߙߊߞߏ ߛߘߌ߬ߜߋ߲ ߞߐߜߍ ߟߎ߬ ߘߐ߫.
 * - ߞߍ߫ ߕߐ߯ߛߓߍߣߍ߲ ߘߌ߫ ߛߊ߲ߝߍ߬߸ ߛߘߌ߬ߜߋ߲ ߏ߬ ߘߌ߫ ߞߙߊߞߏ:ߕߐ߮ ߣߐ߬ߘߐߓߌ߬ߟߊ߬ ߖߝߊߕߌ߫߹ ߕߎ߬ߡߊ߬ ߟߊ߫߸ ߞߙߊߞߏ ߛߘߌ߬ߜߋ߲ ߴߴߟߊߘߏ߲߬ߣߍ߲߬ߴߴ ߦߋ߫ ߞߐߜߍ ߡߍ߲ ߠߎ߬ ߟߊ߫. ߛߘߌ߬ߜߋ߲ ߘߌ߫ ߞߍ߫ ߦߟߍ߬ߡߊ߲߬ߓߊ߬ߟߌ߬ߦߊ ߘߐ߫ ߞߐߜߍ ߟߎ߬ ߓߐߖߎ ߟߊ߫.
 * - ߦߋ߫ ߟߊߘߏ߲߬ ߠߊ߫ ߟߋ߬ ߞߊ߬ ߣߘߐ߬ߓߌ߬ߟߊ߬ߟߌ ߟߊߘߤߊ߬ ߡߍ߲ ߕߍ߫ ߥߊ߬ߟߊ߲߬ߞߌ߬ߟߌ߬ ߗߌߙߏ߲ߣߍ߲߫ ߘߌ߫߸ ߣߌ߲߬ w:en:Help:Substitution ߘߐߜߍ߫.
 * ߦߋ߫ ߟߊߘߏ߲߬ ߠߊ߫ ߞߙߊߞߏ ߟߊ߫ ߟߋ߬ ߛߴߊ߬ ߘߌ߫ ߓߐ߫ ߖߙߎߡߎ߲߫ ߘߐ߫ ߡߍ߲ ߦߋ߫ ߓߊ߯ߙߊ߫ ߟߊ߫ ߥߞߌ ߟߊߞߊ߬ߝߏ߬ߣߍ߲ ߠߊ߫ ߞߊ߬ (syntax) ߛߍ߲ߕߊߞߛ (ߦߏ߫   ߦߋ߫ ߡߍ߲ ߞߍ߫ ߟߊ߫) ߣߵߊ߬ ߦߋ߫ ߞߐߜߍ ߘߴߏ߬ ߘߴߊ߬ ߖߊ߬ߛߏ߲߬.

ߞߍߟߌ ߘߐ߫߸ ߥߞߌ߫ ߡߊߟߐ߲ߣߍ߲ ߞߐߜߍ ߟߎ߬ ߝߣߊ߫ ߘߌ߫ ߛߋ߫ ߟߊߓߊ߯ߙߊ߫ ߟߊ߫ ߞߙߊߞߏ ߘߌ߫߸ ߞߊ߬ ߕߐ߯ߛߓߍߞߣߍ ߞߙߍߞߙߍ߫ ߜߊ߲߯ߛߊ߲߫ ߠߊ߫ ߊ߬ ߢߊߞߍߣߍ߲߫ ߡߍ߲ ߘߐ߫߸ ߏ߬ ߘߐ߫ ߞߊ߬:


 * ߟߊߘߏ߲߬  ߟߊߘߏ߲߬
 * ߟߊߘߏ߲߬
 * ߣߐ߬ߘߐߓߌ߬ߟߊ߫ ߊ߬ ߖߘߍ߬ ߟߊ߫  ߞߣߐߘߐ ߟߊ߫.

ߣߌ߫ ߕߐ߯ ߞߣߍ߫ ߛߎ߮ ߏ߬ ߡߊ߫ ߞߍ߫ ߦߋ߲߬߸ ߞߎ߲߬ߕߐ߮ ߏ߬ ߟߎ߬ ߟߊߞߊ߬ߝߏ߬ߣߍ߲ ߞߊߞߊ߲߫ ߞߊ߬ ߞߍ߫ ߞߙߊߞߏ ߘߌ߫:


 * ߟߊߘߏ߲߬

ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ
To enrich the mechanism of transclusion, MediaWiki allows parameters to be passed to a template when it is transcluded. Parameters allow the template to produce different contents or have different behaviors.

ߌ ߞߊߞߊ߲߫ ߞߊ߬ ߌ ߣߌ߫ ߗߋ߫ ߞߎ߲߬ߕߐ߮ ߞߟߏ ߟߊߘߏ߲߬ ߟߊ߬ߓߊ߰ߙߊ߬ߟߊ߫ ߞߐߜߍ ߟߎ߬ ߟߊ߫ ߞߎߡߊ߫ ߞߐߜߍ ߘߐ߫߸ ߦߏ߫ ߕߊ߲߫:

ߌ ߣߌ߫ ߗߋ߫ ߛߓߍߟߌ ߞߎ߲߭ ߦߋ߫ (ߦߙߐ ߣߌ߲߬ ߠߋ ߘߌ߫߸ ߴߴߌ ߟߊ߫ ߛߋߞߏߦߊ ߓߍ߯ ߟߊ߫ߴߴ) ߊ߬ ߣߌ߫ ߞߟߊ߬ߣߐ (ߒߠߋ). ߌ ߟߊ߫ ߝߋ߲ ߏ߬ ߦߋ߫ ߟߋ߬߸ ߟߊ߬ߓߊ߰ߙߊ߬ߟߊ ߓߍ߯ ߘߌ߫ ߛߋ߫ ߌ ߣߌ߫ ߗߋ ߗߋ߫ ߟߊ߫ ߟߊ߬ߓߊ߰ߙߊ߬ߟߊ߫ ߜߘߍ߫ ߡߊ߬߸ ߞߎ߲߬ ߜߘߍ ߛߎ߯-ߎ-ߛߎ߫ ߣߌ߫ ߦߙߐ ߛߎ߯-ߎ-ߛߎ߫ ߘߐ߫.

ߏ߬ ߘߐ߫ ߛߍߓߟߌ ߟߎ߬ ߘߌ߫ ߡߎߣߎ߲ߧߊ߫ ߦߙߐ ߓߍ߯ ߘߐ߫ ߊ߬ ߟߊߓߊ߯ߙߊߣߍ߲߫ ߡߍ߲ ߘߐ߫߸ ߌ ߘߌ߫ ߛߋ߫ ߞߙߊߞߏ ߘߏ߫ ߡߊߕߍ߰ ߟߊ߫ ߡߍ߲ ߦߋ߫ ߞߟߌ߫ ߟߊ߫ ߞߏ߫, ߞߵߏ߬ ߞߍ߫ ߟߊߒߡߊ ߘߌ߫. ߛߓߍߟߌ ߘߌ߫ ߡߎߣߎ߲߫ ߢߐ߲߯ ߠߊ߫ ߕߋ߲߬ ߝߛߊߦߌ߫߹ ߣߌ߫ ߟߊ߬ߓߊ߰ߙߊ߬ߟߊ ߘߏ߫ ߞߊ߬ ߟߊ߬ߓߊ߰ߙߊ߬ߟߊ߫ ߓߏߙߌߞߊߓߌߟߊ߫߸ ߊ߬ ߞߣߐߘߐ߫ ߞߙߍߞߙߍߣߍ߲ ߠߎ߬ (ߏ߬ ߞߘߐ ߦߋ߫ ߡߍ߲ ߘߌ߫߸ ߊ߬ ߞߎ߲߭ ߣߴߊ߬ ߞߟߊ߬ߣߐ) ߟߎ߬ ߘߌ߫ ߝߘߏ߬ ߢߐ߲߮ ߡߊ߬. ߞߎ߲߭ ߏ߬ ߟߋ ߞߏߛߐ߲߬߸ ߌ ߞߊ߲ߞߊ߲߫ ߞߵߊ߬ߟߎ߫ ߟߊߕߊ߬ߡߌ߲߬ ߞߵߊ߬ߟߎ߫ ߞߍ߫ ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ ߟߎ߬ ߘߌ߫. If we ignore the remaining elements to format the box and place the image, the core content of the template will be this:

ߌ ߦߟߌߣߐ ߕߏ߫  ߟߊߓߊ߯ߙߊ ߡߵߊ߬ ߣߌ߫. ߏ߬ ߦߋ߫ ߛߌߟߊ߫ ߡߊߟߐ߲ߕߊ߫ ߟߋ߬ ߘߌ߫ ߞߙߊߞߏ߫ ߞߏ ߘߐ߫߸ ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ ߡߍ߲ ߞߊߞߊ߲߫ ߞߊ߬ ߟߊߕߊ߬ߡߌ߲߬ ߊ߬ ߘߐ߫ ߣߌ߫ ߞߙߊߞߏ ߟߊߓߊ߯ߙߊ߫ ߘߊ߫. ߏ߬ ߦߟߌߣߐ ߕߊ߬ ߞߙߊߞߏ߫ ߞߏ ߘߐ߫߸ ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ ߓߍ߯ ߟߊߡߌߣߌ߲ߣߍ߲߫ ߦߋ߫ ߜߌߙߌ߲ߘߌߛߓߍߢߌ߲ߞߏ߫: ߜߌߙߌ߲ߘߌߛߓߍߢߌ߲ߞߏ߫$ ߛߊ߬ߓߊ߫ ߟߋ߬ ߟߊ߫. ߏ߬ ߞߏ߬ߣߌ߲߫ ߓߐߣߍ߲߫ ߦߋ߫ ߞߙߊߞߏ ߢߊߓߘߍ ߕߐ߮ ߟߊߓߊ߯ߙߊ ߡߊ߬.

ߣߴߌ ߦߋ߫ ߞߙߊߞߏ ߟߊߓߊ߯ߙߊ ߞߊ߲߬ ߞߐߜߍ ߞߊ߲߬߸ ߌ ߦߋ߫ ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ ߡߐ߬ߟߐ߲ ߟߝߊ߫߸ ߡߍ߫ ߕߍߝߘߊߣߍ߲߫ ߦߋ߫ ߔߌߔ (ߔߊߔ$) ߟߊ߫. ߡߋߘߌߦߊߥߞߌ߫ ߘߌ߫ ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ ߟߊߘߌ߬ߢߍ߬ ߞߊ߬ ߛߋ߫ ߕߊ߬ߡߌ߲߬ ߠߊ߫ ߞߊ߬ ߞߍ߫ ߞߙߊߞߏ ߘߌ߫ ߛߌߟߊ߫ ߛߊ߬ߓߊ߫ ߞߊ߲߫: ߕߐ߯ߒߕߊ߲ߧߊ ߘߐ߫߸ ߝߙߍߕߍߦߊ ߘߐ߫߸ ߊ߬ ߣߌ߫ ߕߐ߯ߦߊߟߌ ߘߐ߫.

ߕߐ߯ߒߕߊ߲ߧߊ ߟߊ߬ߓߍ߲߬ߢߐ߲߰ߡߦߊ߬ߘߊ
To pass in anonymous parameters, list the values of those parameters sequentially:

In this case, the  template receives parameters   and , producing:

The order in which anonymous parameters are passed in is crucial to its behavior. Reversing the order of the parameters, like so:

would produce this result:

Numbered parameters
To pass in parameters by number, identify each parameter when passing it:

This time, template  receives parameters   and , though they have been supplied in inverse order, and produces:

Named parameters
The third way of passing parameters is by name instead of numbers. In this case, the template contents would be changed to:

A little thank you... for. hugs,

Within the template, we use  and   to identify each parameter, instead of a number. To pass these parameters by name, identify each parameter when passing it:

In this case, template  receives parameters   and   and produces:

Named parameters are case-sensitive, so:

produces:

The advantage of using named parameters in your template, besides also being flexible in the order parameters can be passed, is that it makes the template code much easier to understand if there are many parameters.

Default values
If you transclude a template that expects parameters, but do not provide their arguments, in this way:

in the numbered parameters example above you would get the following:

Since no arguments were passed in, the template presents the parameters themselves, instead of their respective values. In these cases, it may be useful to define default values for the parameters, i.e. values that will be used if no value is passed in. For example, if the template contents are changed to:

then  defines that if no argument is provided for parameter , then the value   will be used. Similarly,, defaults parameter   to value. Now, transcluding the template again without passing any argument results in the following:

Often default values are used to specify alternate names of parameters. For example, if you have, the template will first look for a parameter named "a". If it is not set, it will use the parameter named "b". If neither "a" nor "b" is set, it will output nothing.

Evaluation
Generally speaking, template parameters are substituted into the template after tokenization, but as is. They are not evaluated until they are used.

This has a few consequences. First of all, if you have a  containing , and a   containing  , and put   on a page, mytemplate isn't transcluded, because tokens like "|" cannot be added by a template and keep their special meaning in templates. You can still use templates to control the name of a parameter or template, but you cannot split a template call amongst multiple templates.

The second consequence of this is dead-code elimination. If you make a template call like, and Template:Foo does not contain  , then the displaytitle is not used, since it is only evaluated when needed, and it there is no parameter to substitute it into, so it is never evaluated. This usually comes into play when using Extension:ParserFunctions, and can be especially noticed when used in combination with the  magic word that varies by user language.

Template calls starting with the magic word  or   are evaluated in a separate first pass that only happens at save time, along with ~ and links using the pipe trick. If they cannot be evaluated during the first pass, subst: calls are ignored, and safesubst: are treated as if a normal template.

Many but not all parser functions, parser tags and trancluded special pages are not directly included like templates but instead are replaced by a "strip marker". This means you cannot manipulate the results with parser functions like padleft: or similar functions from extensions, as they see the strip marker instead of the result of the parser function.

Recursion in templates
Including a template in itself won't throw MediaWiki into infinite recursion. MediaWiki will stop the recursion with the template's name in bold. For example, if the content of "Template:Aaaa" is " ", it'll show as "Template:Aaaa" and display Template loop detected: Template:Aaaa.

Control template inclusion
By default, a template's content is displayed in its entirety, both when viewed directly and when included in another page. However, you can control which parts of a template will be seen and included by the use of the,   and   tags.

Anything between  and   will be seen only when the template's page is being viewed directly, but not when it is included in another page. This is useful when you want to include text or code in a template that you do not want to propagate to any pages which include it, such as:


 * Category links when categorizing the template itself
 * interlanguage links to similar templates in other languages
 * Explanatory text about how to use the template

Likewise, anything between  and   will be processed and displayed only when the page is being included, but not when the template page is being viewed directly, and is useful in situations such as:


 * Categorizing pages which include the template. Note: when changing the categories applied by a template in this fashion, the categorization of the pages which include that template may not be updated until some time later: this is handled by the . To force the re-categorization of a particular page, open that page for editing and save it without changes.
 * Ensuring that the template's code is not executed when viewing the template page itself. Typically this is because it expects parameters, and its execution without parameters has an undesired result.

Everything outside  and   is processed and displayed normally; that is, both when the template page is being viewed directly and when the template is included in another page. The focus is on what is inside these two tags.

Everything outside  tags is discarded in the transclusion. Even sections tagged includeonly are discarded in the transclusion unless they are also tagged as onlyinclude. The focus is on what is outside this tag.

Nesting of these tags is also possible.

The three partial transclusion tags enable all possible combinations of what is processed and rendered. Comments also fill a role.

Organizing templates
For templates to be effective, users need to find them, and find out how to use them.

To find them, users can:
 * 1) Click ' > '
 * 2) In the ' list, choose Template and click '.

To give usage information, include an example like this one on the template page:

Usage
Welcome users:

Then, an editor can simply copy and paste the example to use the template.

Linking to a template
A template page can be linked to like any other wiki page. For example, the link is generated using the wikicode.

On many wikis, Template:Tl can be used to provide a link to a template formatted in a way that shows the "double curly-braces" wikicode necessary to transclude the template without actually doing the tranclusion. For example, the code  may be used to create the link Navbar.

This construct is commonly used in template documentation, on help pages, and on talk pages when referring to templates. The same effect can be achieved by using, but the tl approach involves much less typing. On any given wiki the Tl template, if it exists, may or may not render the text in a "code" element, as shown here. If not, another similarly named template may do so. See, for example, the "See also" section of the documentation of en:Template:Tl at the English Wikipedia.

Copying from one wiki to another
Templates often require CSS or other templates, so users frequently have trouble copying templates from one wiki to another. The steps below should work for most templates.

MediaWiki code
If you have import rights (Specifically importupload) on the new wiki:


 * 1) Go to Special:Export on the original wiki, and download an .xml file with the complete history of all necessary templates, as follows:
 * 2) * Enter the name of the template in the big text box, e.g. "Template:Welcome". Pay special attention to capitalization and special characters — if the template name isn't exactly correct, the export may still occur but the .xml file will not have the expected data.
 * 3) * Check the box "".
 * 4) * Uncheck the box "".
 * 5) * Click "".
 * 6) Go to Special:Import on the new wiki and upload the .xml file.

If you don't have import rights on the new wiki:


 * 1) Go to the template you want to copy from the original wiki. Go to the edit page, and copy all the wikitext
 * 2) On the new wiki, go to the page with the same name as the template you copied. Hit create/edit and paste the wikitext you copied. In the edit summary of each template, link to the original page for attribution.
 * 3) Back in the original wiki at the edit window, below the edit box, look at the list of "Templates used on this page". For each template listed follow these instructions. Also do that for any template used by any of these templates, and so on.

This will copy the entire code necessary, and will suffice for some templates. If it doesn't work also check for red links listed under "Pages transcluded onto the current version of this page:", below the edit box. If there are any repeat the above steps for these as well and also copy the code in the modules.

After successfully importing the template and all its linked templates from the other wiki, edit it to change customisations to suit your wiki. For example to change a logo, remove redundant categories or red links.

Extensions
An extension often used in templates is ParserFunctions. Visit page and check if any of the functions listed there are used in the templates you've copied. If so, you have to install the extension. To install it, you'll need system admin access to the server of your MediaWiki installation.

Another dependency that may be used in templates, especially those on Wikipedia, is Lua. Having   in template code is a good sign for it. In case it's used, you need to install the extension and system admin access is required too. See that page for more instructions about installing and using the extension.

CSS and JavaScript code
Besides MediaWiki code, many templates make use of CSS and some rely on JavaScript to work fully. If the copied templates are not behaving as expected, this may be the cause. To copy the required CSS and JavaScript to your wiki you'll normally need to have admin privileges, because you'll be editing system messages in the "MediaWiki:" namespace.


 * 1) Look for the use of CSS classes (text like  ) in the template text. If those classes appear in "MediaWiki:Common.css" or "MediaWiki:Monobook.css" on the original wiki, copy those classes to "MediaWiki:Common.css" on the new wiki and check if the template is now fine.
 * 2) If the copied template is still not working as expected, check if there is code in "MediaWiki:Common.js" or "MediaWiki:Monobook.js" on the original wiki. If so, you can try copying it to "MediaWiki:Common.js" on the new wiki. Normally, it is a good idea to only copy code from trusted sources, and first browsing the code to identify and select the parts that are relevant. You may find comments that can serve as clues to identify the functionality of each part.