Editing Template:If/doc (section)

==Performance considerations==
Because [[Template:If]] must prepare the parameters for <code>#if, #ifeq, #ifexpr,</code> (etc.) there is a slight overhead when using it. Each nested use adds 5 levels to the template expansion depth, so 7 nested if-templates would use 35 levels (5*7) of the [[m:Help:Expansion_depth|41-level limit]].

'''Using P-if syntax:''' A similar if-structure can be coded without '''Template:If''', by using the {{tlx|P1}} and {{tlx|P2}} templates in a "P-if" structure. [[Template:P1]] always returns parameter 1, and P2 returns the 2nd. So, a comparison of 4 versus 3 can be coded using P-if syntax form:
:: Example of <code>#ifexpr</code>: <syntaxhighlight lang="text" inline>"{{P{{#ifexpr: 4 > 3|1|2}}| then 4 greater| else 4 lower}}"</syntaxhighlight>
:: Result for <code>#ifexpr</code>: &nbsp; "{{P{{#ifexpr: 4 > 3|1|2}}| then 4 greater| else 4 lower}}" &larr; ''the comparison invoked'' {<nowiki/>{P1}}.
The expansion depth of a P-if is only 4 levels deep, but nesting of the then-clause or else-clause might be more confusing than using nested levels of Template:if.

:: Example of <code>#if</code>: <syntaxhighlight lang="text" inline>"{{P{{#if:{{{2|x}}}|1|2}}| then {2} set| else {2} empty}}"</syntaxhighlight>
:: Result for <code>#if</code>: "{{P{{#if:{{{2|}}}|1|2}}| then {2} set| else {2} empty}}" &larr; ''the comparison invoked'' {<nowiki/>{P2}}.