{{Yesno}} (or{{YesNo}}) evaluates any input and produces a normalizedyes or nil output, based on the content of the input and several configurable options. It is not used in article prose, but in coding complex templates.
Usage
The template distinguishes five different types of input, supplied on the first unnamed parameter:
Yes: Case-insensitive forms ofYes,y,true,on, and1; e.g.{{Yesno|yEs}} → yes
No: Case-insensitive forms ofNo,n,false,off, and0; e.g.{{Yesno|nO}} →
Nothing: When the input is defined but either contains no value or consists ofwhitespace character only; i.e.{{Yesno|}} or{{Yesno| }} →
Negation: When the input is either¬ (alt code170) or entirely missing; i.e.{{Yesno|¬}} or{{Yesno}} →
By default, the template returns "yes" in the first and last case but returns nil (blank, empty string) in the other cases.
Two short-hand templates for the most common uses that override the default behavior:
{{yesno-yes}} or{{YesNo-Yes}} – always returns "yes" (or the specified replacement result in|yes=) unless an explicit negative value is given; i.e., it evaluates to "yes" even when the value is empty or missing.
{{yesno-no}} or{{YesNo-No}} – always returns "no" (or the specified replacement result in|no=) unless an explicit positive value is given; i.e., it evaluates to "no" even when the value is present, as long as it does not contain anything that resolves to "yes".
Customizing the output
Template's default output can be customized with five named parameters, respectively:|yes=,|no=,|blank=,|¬= and|def=. If these parameters are specified, the template response is as follows:
Yes: Template returns the contents of|yes=, otherwise returns "yes". For example:
Anything else: Template returns the contents of|def=, or of|yes= in absence of the former; otherwise, returns "yes".
{{yesno|purple monkey dish washer|def=cup of tea}} results in "cup of tea"
{{yesno|purple monkey dish washer|yes=bacon}} results in "bacon"
{{yesno|purple monkey dish washer|def=cup of tea|yes=bacon}} results in "cup of tea"
For the named parameters, use of a blank value is not the same as omitting the parameter. A blank named parameter tells the template that the customized return value is blank. For example:
{{yesno|purple monkey dish washer}} results in "yes"
{{yesno|purple monkey dish washer|def=}} results in ""[blank]
Logical distinctions
Overview of{{yesno}}logical values and their associated texts
Input parameter 1 (1=)
In code
Logical return value
Default return text
Return text when set: yes=Pos no=Neg blank=Blank ¬=Undefined def=Def
Unnamed parameter 1= the input value to be evaluated. The other parameters (all named, all optional), are thereturn values for their respective logical outcome. When set, each one overrules theirdefault return value.
{{yesno |Input value |yes =Output on yes |no =Output on no |blank =Output on blank input |¬ =Output on ¬ |def =Definite output }}
