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Hëllef:Erweiderung:ParserFunktiounen

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This page is a translated version of the page Help:Extension:ParserFunctions and the translation is 4% complete.

The ParserFunctions extension provides additional parser functions to supplement the "magic words ", which are already present in MediaWiki. (Sie kann konfiguriert werden, um zusätzliche Parser-Funktionen zur Vearbeitung von Strings zur Verfügung zu stellen, diese sind anderswo dokumentiert.) All the parser functions provided by this extension take the form:

{{#functionname: argument 1 | argument 2 | argument 3 ... }}
PD Notiz: Wann Dir dës Säit ännert sidd Dir d'accord Är Kontributioun ënner der CC0 ze publizéieren. Kuckt Public Domain Hëllefsäite fir méi Informatiounen. PD

#expr

For a more in-depth manual on the finer points of how the expression evaluator works, including some additional operators not covered here, see: Manual:Expr parser function syntax.
Typ Operators
Grouping (parentheses) ( )
Zuelen 1234.5   e (2.718)   pi (3.142)
binary operator e   unary +,-
Unary not ceil trunc floor abs exp ln sin cos tan acos asin atan sqrt
Binary ^
* / div mod fmod
+ -
Round round
Logic = != <> > < >= <=
and
or

This function evaluates a mathematical expression and returns the calculated value. This function is also available in Scribunto via the mw.ext.ParserFunctions.expr function.

{{#expr: expression }}

Basic example

{{#expr: 1 + 1 }}2

The available operators are listed to the right, in order of precedence. See Manual:Expr parser function syntax for more details of the function of each operator. The accuracy and format of the result returned will vary depending on the operating system of the server running the wiki and the number format of the site language.

When evaluating using boolean algebra, zero evaluates to false, and any nonzero value, positive or negative, evaluates to true:

{{#expr: 1 and -1 }}1
{{#expr: 1 and 0 }}0
{{#expr: 1 or -1 }}1
{{#expr: -1 or 0 }}1
{{#expr: 0 or 0 }}0

An empty input expression returns an empty string. Invalid expressions return one of several error messages, which can be caught using the #iferror function:

{{#expr: }}
{{#expr: 1+ }}Expression error: Missing operand for +.
{{#expr: 1 = }}Expression error: Missing operand for =.
{{#expr: 1 foo 2 }}Expression error: Unrecognized word "foo".

The order of addition and subtraction operands before or after a number is meaningful and may be treated as a positive or negative value instead of as an operand with an erroneous input:

{{#expr: +1 }}1
{{#expr: -1 }}-1
{{#expr: + 1 }}1
{{#expr: - 1 }}-1

Note, if using the output of magic words, you must raw-format them in order to remove commas and translate the numerals. For example, {{NUMBEROFUSERS}} results in 18.013.991, where we want 18013991, which can be obtained using {{formatnum :{{NUMBEROFUSERS}}|R}}. This is especially important in some languages, where numerals are translated. For example, in Bengali, {{NUMBEROFUSERS}} produces ৩০,০৬১.

{{#expr:{{NUMBEROFUSERS}}+100}} 118.013
{{#expr:{{formatnum:{{NUMBEROFUSERS}}|R}}+100}}18014091
Warning Warning: The operator mod gives wrong results for some values of the second argument:
{{#expr: 123 mod (2^64-1)}}Division by zero. (produces an empty string; should be 123)
If you want to do calculations based on dates (ex. test whether current date and time is after some other date and time), first convert the time to number of seconds after January 1, 1970 (UTC) using {{#time: xNU }}, then you can simply add and subtract dates as numbers.

Op- an Ofronnen

Rounds off the number on the left to a multiple of 1/10 raised to a power, with the exponent equal to the truncated value of the number given on the right.

To round up or down use unary ceil or floor respectively.

Test case Resultat Method of rounding
{{#expr: 1/3 round 5 }} 0.33333 Final digit is < 5, so no apparent rounding occurs (0.333333… → 0.33333)
{{#expr: 1/6 round 5 }} 0.16667 Final digit is ≥ 5, so it is rounded up (0.166666… → 0.16667)
{{#expr: 8.99999/9 round 5 }} 1 Again, the result is rounded up on the last digit, which results in additional rounding (0.999998… → 1.00000 → 1)
{{#expr: 1234.5678 round -2 }} 1200 Rounded to nearest 100 because negative values round to the left of the decimal point
{{#expr: 1234.5678 round 2 }} 1234.57 Rounded to nearest 100th because positive values round to the right of the decimal point
{{#expr: 1234.5678 round 2.3 }} 1234.57 Decimals in the rounding index make no difference in the rounded result
{{#expr: trunc 1234.5678 }} 1234 Decimal portion truncated (chopped off)
Rounding to the nearest integer
{{#expr: 1/3 round 0 }} 0 Down to the nearest integer, which is zero
{{#expr: 1/2 round 0 }} 1 Up to the nearest integer, which is one
{{#expr: 3/4 round 0 }} 1 Up to the nearest integer, which is one
{{#expr: -1/3 round 0 }} -0 Up to the nearest integer, which is zero
{{#expr: -1/2 round 0 }} -1 Down to the nearest integer, which is negative one
{{#expr: -3/4 round 0 }} -1 Down to the nearest integer, which is negative one
Rounding up or down with ceil and floor
{{#expr: ceil(1/3) }} 1 Up to the next larger integer, which is one
{{#expr: floor(1/3) }} 0 Down to the next smaller integer, which is zero
{{#expr: ceil(-1/3) }} -0 Up to the next larger integer, which is zero
{{#expr: floor(-1/3) }} -1 Down to the next smaller integer, which is negative one
{{#expr: ceil 1/3 }} 0.33333333333333 Not rounded, since 1 already is an integer
Warning Warning: Interpreted as (ceil 1)/3, not ceil(1/3), as you might expect
Rounding large numbers
{{#expr: 1e-92 round 400 }} 1.0E-92 Rounding to a very large number leads to infinity. Hence, the original value without the infinity is given as the answer.
{{#expr: 1e108 round 200 }} 1.0E+108 Same as above.

Strings

Expressions only work with number-like values, they cannot compare strings or characters. #ifeq can be used instead.

{{#expr: "a" = "a" }}Expression error: Unrecognized punctuation character """.
{{#expr: a = a }}Expression error: Unrecognized word "a".
{{#ifeq: a | a | 1 | 0 }}1

#if

This function evaluates a test string and determines whether or not it is empty. A test string containing only white space is considered to be empty.

{{#if: test string | value if test string is not empty | value if test string is empty (or only white space)}}
{{#if: éischte Parameter | zweete Parameter | drëtte Parameter }}

This function first tests whether the first parameter is not empty. If the first parameter is not empty, the function displays the second argument. If the first parameter is empty or contains only whitespace characters (spaces, newlines, etc.) it displays the third argument.

{{#if: | yes | no}}no
{{#if: string | yes | no}}yes
{{#if: &nbsp;&nbsp;&nbsp;&nbsp; | yes | no}}no
{{#if: | yes | no}}no

The test string is always interpreted as pure text, so mathematical expressions are not evaluated (see #ifexpr for that):

{{#if: 1==2 | yes | no }}yes
{{#if: 0 | yes | no }}yes

The last parameter (false) may be omitted:

{{#if: foo | yes }} yes
{{#if: | yes }}
{{#if: foo | | no}}

The function may be nested. To do so, nest the inner #if function in its full form in place of a parameter of the enclosing #if function. Up to seven levels of nesting is possible, although that may depend on the wiki or a memory limit.

{{#if:test string
|value if test string is not empty
|{{#if:test string
  |value if test string is not empty
  |value if test string is empty (or only white space)
  }}
}}

You can also use a parameter as the test string in your #if statement. You need to ensure you add the | (pipe symbol) after the name of the variable. (So that if the parameter does not have a value, it evaluates to an empty string instead of the string "{{{1}}}".)

{{#if:{{{1|}}}|You entered text in variable 1|There is no text in variable 1}}

See Help:Parser functions in templates for more examples of this parser function.

#ifeq

This parser function compares two input strings, determines whether they are identical, and returns one of two strings based on the result. If more comparisons and output strings are required, consider using #switch.

{{#ifeq: string 1 | string 2 | value if identical | value if different }}

If both strings are valid numerical values, the strings are compared numerically:

{{#ifeq: 01 | 1 | equal | not equal}}equal
{{#ifeq: 0 | -0 | equal | not equal}}equal
{{#ifeq: 1e3 | 1000 | equal | not equal}}equal
{{#ifeq: {{#expr:10^3}} | 1000 | equal | not equal}}equal

Otherwise, the comparison is made as text; this comparison is case-sensitive:

{{#ifeq: foo | bar | equal | not equal}}not equal
{{#ifeq: foo | Foo | equal | not equal}}not equal
{{#ifeq: "01" | "1" | equal | not equal}}not equal  (compare to similar example above, without the quotes)
{{#ifeq: 10^3 | 1000 | equal | not equal}}not equal  (compare to similar example above, with #expr returning a valid number first)

As a practical example, consider an existing template Template:Timer using the parser to choose between two standard times, short and long. It takes the parameter as the first input to compare against the string "short" – there is no convention for the order, but it is simpler to read if the parameter goes first. The template code is defined as:

{{#ifeq: {{{1|}}} | short | 20 | 40 }}

the following ensue:

{{timer|short}}20
{{timer|20}}40
{{timer}}40
Warning Warning: When used inside a parser function, any parser tags and other parser functions must be temporarily replaced with a unique code . This affects comparisons:
{{#ifeq: <nowiki>foo</nowiki> | <nowiki>foo</nowiki> | equal | not equal}}not equal
{{#ifeq: <math>foo</math> | <math>foo</math> | equal | not equal}}not equal
{{#ifeq: {{#tag:math|foo}} | {{#tag:math|foo}} | equal | not equal}}not equal
{{#ifeq: [[foo]] | [[foo]] | equal | not equal}}equal

If the strings to be compared are given as equal calls to the same template containing such tags, then the condition is true, but in the case of two templates with identical content containing such tags it is false.

Warning Warning: Literal comparisons to page-name magic words may fail depending on site configuration. For example, {{FULLPAGENAME}}, depending on wiki, may capitalize the first letter, and will replace all underscores with spaces.

To work around this, apply the magic word to both parameters:

{{#ifeq: {{FULLPAGENAME: L'Aquila}} | {{FULLPAGENAME}} | equal | not equal}}equal

#iferror

This function takes an input string and returns one of two results; the function evaluates to true if the input string contains an HTML object with class="error", as generated by other parser functions such as #expr, #time and #rel2abs, template errors such as loops and recursions, and other "failsoft" parser errors.

{{#iferror: test string | value if error | value if correct }}

One or both of the return strings can be omitted. If the correct string is omitted, the test string is returned if it is not erroneous. If the error string is also omitted, an empty string is returned on an error:

{{#iferror: {{#expr: 1 + 2 }} | error | correct }}correct
{{#iferror: {{#expr: 1 + X }} | error | correct }}error
{{#iferror: {{#expr: 1 + 2 }} | error }}3
{{#iferror: {{#expr: 1 + X }} | error }}error
{{#iferror: {{#expr: 1 + 2 }} }}3
{{#iferror: {{#expr: 1 + X }} }}
{{#iferror: {{#expr: . }} | error | correct }}correct
{{#iferror: <strong class="error">a</strong> | error | correct }}error

Some errors may cause a tracking category to be added, using {{#iferror:}} will not suppress the addition of the category.

#ifexpr

This function evaluates a mathematical expression and returns one of two strings depending on the boolean value of the result:

{{#ifexpr: expression | value if true | value if false }}

The expression input is evaluated exactly as for #expr above, with the same operators being available. The output is then evaluated as a boolean expression.

An empty input expression evaluates to false:

{{#ifexpr: | yes | no}}no

As mentioned above, zero evaluates to false and any nonzero value evaluates to true, so this function is equivalent to one using #ifeq and #expr only:

{{#ifeq: {{#expr: expression }} | 0 | value if false | value if true }}

except for an empty or wrong input expression (an error message is treated as an empty string; it is not equal to zero, so we get value if true).

{{#ifexpr: = | yes | no }} Expression error: Unexpected = operator.

vergläichen

{{#ifeq: {{#expr: = }} | 0 | no | yes }} yes

Either or both of the return values may be omitted; no output is given when the appropriate branch is left empty:

{{#ifexpr: 1 > 0 | yes }}yes
{{#ifexpr: 1 < 0 | yes }}
{{#ifexpr: 0 = 0 | yes }} yes
{{#ifexpr: 1 > 0 | | no}}
{{#ifexpr: 1 < 0 | | no}} no
{{#ifexpr: 1 > 0 }}

Boolean operators of equality or inequality operators are supported.

{{#ifexpr: 0 = 0 or 1 = 0 | yes}}yes
{{#ifexpr: 0 = 0 and 1 = 0 | | no}}no
{{#ifexpr: 2 > 0 or 1 < 0 | yes}}yes
{{#ifexpr: 2 > 0 and 1 > 0 | yes | no}}yes
Warning Warning: The results of numerical comparisons with #ifexpr do not always match those of #ifeq and #switch. These latter two are more accurate than #ifexpr, and so may not return equivalent results.

Consider these comparisons with the final digit changed:

{{#ifeq: 12345678901234567 | 12345678901234568 | equal | not equal}}not equal
{{#switch: 12345678901234567 | 12345678901234568 = equal | not equal}}not equal

Because PHP used in #ifeq and #switch compares two numbers of type integer, it returns the expected result correctly. Whereas with #ifexpr and the same numbers:

{{#ifexpr: 12345678901234567 = 12345678901234568 | equal | not equal}}equal

With the different digit, the result of equal is actually incorrect.

This behaviour in #ifexpr is caused because MediaWiki converts literal numbers in expressions to type float, which, for large integers like these, involves rounding.

#ifexist

See Manual:Checking for page existence for other methods of checking if a page exists with different limitations

This function takes an input string, interprets it as a page title, and returns one of two values depending on whether or not the page exists on the local wiki.

{{#ifexist: page title | value if exists | value if doesn't exist }}

The function evaluates to true if the page exists, whether it contains content, is visibly blank (contains meta-data such as category links or magic words , but no visible content), is blank, or is a redirect . Only pages that are redlinked evaluate to false, including if the page used to exist but has been deleted.

{{#ifexist: Help:Extension:ParserFunctions/lb | exists | doesn't exist }}exists
{{#ifexist: XXHelp:Extension:ParserFunctions/lbXX | exists | doesn't exist }}doesn't exist

The function evaluates to true for system messages that have been customized, and for special pages that are defined by the software.

{{#ifexist: Special:Watchlist | exists | doesn't exist }}exists
{{#ifexist: Special:CheckUser | exists | doesn't exist }}exists (because the Checkuser extension is installed on this wiki)
{{#ifexist: MediaWiki:Copyright | exists | doesn't exist }}doesn't exist (because MediaWiki:Copyright has not been customized)

If a page checks a target using #ifexist:, then that page will appear in the Special:WhatLinksHere list for the target page. So if the code {{#ifexist:Foo }} were included live on this page (Help:Extension:ParserFunctions/lb), Special:WhatLinksHere/Foo will list Help:Extension:ParserFunctions/lb.

On wikis using a shared media repository, #ifexist: can be used to check if a file has been uploaded to the repository but not to the wiki itself:

{{#ifexist: File:Example.png | exists | doesn't exist }}doesn't exist
{{#ifexist: Image:Example.png | exists | doesn't exist }}doesn't exist
{{#ifexist: Media:Example.png | exists | doesn't exist }}exists

If a local description page has been created for the file, the result is exists for all of the above.

#ifexist: funktionéiert net mat Interwiki-tyv

ifexist limits

#ifexist: is considered an "expensive parser function"; only a limited number of which can be included on any one page (including functions inside transcluded templates). When this limit is exceeded, any further #ifexist: functions automatically return false, whether the target page exists or not, and the page is categorized into Category:Pages with too many expensive parser function calls. The name of the tracking category may vary depending on the content language of your wiki.

For some use cases it is possible to emulate the ifexist effect with css, by using the selectors a.new (to select links to unexisting pages) or a:not(.new) (to select links to existing pages). Furthermore, since the number of expensive parser functions that can be used on a single page is controlled by $wgExpensiveParserFunctionLimit , one can also increase the limit in LocalSettings.php if needed.

ifexist and wanted pages

A page that does not exist and is tested for using #ifexist will end up on the Wanted Pages. See task T14019 for the reason, and w:Template:Linkless exists for a workaround.

#rel2abs

This function converts a relative file path into an absolute filepath.

{{#rel2abs: path }}
{{#rel2abs: path | base path }}

Within the path input, the following syntax is valid:

  • .the current level
  • ..go up one level
  • /foogo down one level into the subdirectory /foo

If the base path is not specified, the full page name of the page will be used instead:

{{#rel2abs: /quok | Help:Foo/bar/baz }}Help:Foo/bar/baz/quok
{{#rel2abs: ./quok | Help:Foo/bar/baz }}Help:Foo/bar/baz/quok
{{#rel2abs: ../quok | Help:Foo/bar/baz }}Help:Foo/bar/quok
{{#rel2abs: ../. | Help:Foo/bar/baz }}Help:Foo/bar

Invalid syntax, such as /. or /./, is ignored. Since no more than two consecutive full stops are permitted, sequences such as these can be used to separate successive statements:

{{#rel2abs: ../quok/. | Help:Foo/bar/baz }}Help:Foo/bar/quok
{{#rel2abs: ../../quok | Help:Foo/bar/baz }}Help:Foo/quok
{{#rel2abs: ../../../quok | Help:Foo/bar/baz }}quok
{{#rel2abs: ../../../../quok | Help:Foo/bar/baz }}Fehler: Ungültige Pfadtiefe: „Help:Foo/bar/baz/../../../../quok“ (Zugriff auf einen Knotenpunkt oberhalb des Hauptknotenpunktes ist empfohlen)

For a similar group of functions see also Help:Magic words#URL data. Built-in parser functions include: 'localurl:', 'fullurl:', 'anchorencode:' etc.

#switch

See also: w:Help:Switch parser function

This function compares one input value against several test cases, returning an associated string if a match is found.

{{#switch: comparison string
 | case = result
 | case = result
 | ...
 | case = result
 | default result
}}

Beispill:

{{#switch: baz | foo = Foo | baz = Baz | Bar }} Baz
{{#switch: foo | foo = Foo | baz = Baz | Bar }} Foo
{{#switch: zzz | foo = Foo | baz = Baz | Bar }} Bar

#switch with partial transclusion tags can affect a configuration file that enables an editor unfamiliar with template coding to view and edit configurable elements.

Default

The default result is returned if no case string matches the comparison string:

{{#switch: test | foo = Foo | baz = Baz | Bar }} Bar

In this syntax, the default result must be the last parameter and must not contain a raw equals sign (an equals sign without {{}}). If it does, it will be treated as a case comparison, and no text will display if no cases match. This is because the default value has not been defined (is empty). If a case matches however, its associated string will be returned.

{{#switch: test | Bar | foo = Foo | baz = Baz }} →
{{#switch: test | foo = Foo | baz = Baz | B=ar }} →
{{#switch: test | test = Foo | baz = Baz | B=ar }} → Foo

Alternatively, the default result may be explicitly declared with a case string of "#default".

{{#switch: comparison string
 | case = result
 | case = result
 | ...
 | case = result
 | #default = default result
}}

Default results declared in this way may be placed anywhere within the function:

{{#switch: test | foo = Foo | #default = Bar | baz = Baz }} Bar

If the default parameter is omitted and no match is made, no result is returned:

{{#switch: test | foo = Foo | baz = Baz }}

Grouping results

It is possible to have 'fall through' values, where several case strings return the same result string. This minimizes duplication.

{{#switch: comparison string
 | case1 = result1
 | case2 
 | case3 
 | case4 = result234
 | case5 = result5
 | case6 
 | case7 = result67
 | #default = default result
}}

Here cases 2, 3 and 4 all return result234; cases 6 and 7 both return result67. The "#default = " in the last parameter may be omitted in the above case.

Use with parameters

The function may be used with parameters as the test string. In this case, it is not necessary to place the pipe after the parameter name, because it is very unlikely that you will choose to set a case to be the string "{{{parameter name}}}". (This is the value the parameter will default to if the pipe is absent and the parameter doesn't exist or have a value. See Help:Parser functions in templates .)

{{#switch: {{{1}}} | foo = Foo | baz = Baz | Bar }}

In the above case, if {{{1}}} equals foo, the function will return Foo. If it equals baz, the function will return Baz. If the parameter is empty or does not exist, the function will return Bar.

As in the section above, cases can be combined to give a single result.

{{#switch: {{{1}}} | foo | zoo | roo = Foo | baz = Baz | Bar }}

Here, if {{{1}}} equals foo, zoo or roo, the function will return Foo. If it equals baz, the function will return Baz. If the parameter is empty or does not exist, the function will return Bar.

Additionally, the default result can be omitted if you do not wish to return anything if the test parameter value does not match any of the cases.

{{#switch: {{{1}}} | foo = Foo | bar = Bar }}

In this case, the function returns an empty string unless {{{1}}} exists and equals foo or bar, in which case it returns Foo or Bar, respectively.

This has the same effect as declaring the default result as empty.

{{#switch: {{{1}}} | foo | zoo | roo = Foo | baz = Baz | }}

If for some reason you decide to set a case as "{{{parameter name}}}", the function will return that case's result when the parameter doesn't exist or doesn't have a value. The parameter would have to exist and have a value other than the string "{{{parameter name}}}" to return the function's default result.

(when {{{1}}} doesn't exist or is empty):
{{#switch: {{{1}}} | {{{1}}} = Foo | baz = Baz | Bar }} Foo
(when {{{1}}} has the value "test"):
{{#switch: {{{1}}} | {{{1}}} = Foo | baz = Baz | Bar }} Bar
(when {{{1}}} has the value "{{{1}}}"):
{{#switch: {{{1}}} | {{{1}}} = Foo | baz = Baz | Bar }} Foo

In this hypothetical case, you would need to add the pipe to the parameter ({{{1|}}}).

Comparison behavior

As with #ifeq, the comparison is made numerically if both the comparison string and the case string being tested are numeric; or as a case-sensitive string otherwise:

{{#switch: 0 + 1 | 1 = one | 2 = two | three}} → three
{{#switch: {{#expr: 0 + 1}} | 1 = one | 2 = two | three}} → one
{{#switch: 02 | +1 = one | +2 = two | three}} → two
{{#switch: 100 | 1e1 = ten | 1e2 = hundred | other}} → hundred
{{#switch: a | a = A | b = B | C}} → A
{{#switch: A | a = A | b = B | C}} → C

A case string may be empty:

{{#switch: | = Nothing | foo = Foo | Something }}Nothing

Once a match is found, subsequent cases are ignored:

{{#switch: b | f = Foo | b = Bar | b = Baz | }}Bar
Warning Warning:

Numerical comparisons with #switch and #ifeq are not equivalent to comparisons in expressions (see also above):

{{#switch: 12345678901234567 | 12345678901234568 = A | B}} → B
{{#ifexpr: 12345678901234567 = 12345678901234568 | A | B}} → A

Raw equal signs

"Case" strings cannot contain raw equals signs. To work around this, use the {{=}} magic word, or replace equals sign with HTML code &#61;.

Beispill:

You type You get
{{#switch: 1=2
 | 1=2 = raw
 | 1<nowiki>=</nowiki>2 = nowiki
 | 1{{=}}2 = template
 | default
}}
template
{{#switch: 1=2
 | 1&#61;2 = html
 | default
}}
html
For a simple real life example of the use of this function, check Template:NBA color. Two complex examples can be found at Template:Extension and w:Template:BOTREQ.

Replacing #ifeq

#switch can be used to reduce expansion depth.

For example:

  • {{#switch:{{{1}}} |condition1=branch1 |condition2=branch2 |condition3=branch3 |branch4}}

is equivalent to

  • {{#ifeq:{{{1}}}|condition1 |branch1 |{{#ifeq:{{{1}}}|condition2 |branch2 |{{#ifeq:{{{1}}}|condition3 |branch3 |branch4}}}}}}

i.e. deep nesting, linear:

{{#ifeq:{{{1}}}|condition1
  |<!--then-->branch1
  |<!--else-->{{#ifeq:{{{1}}}|condition2
                |<!--then-->branch2
                |<!--else-->{{#ifeq:{{{1}}}|condition3
                              |<!--then-->branch3
                              |<!--else-->branch4}}}}}}

On the other hand, the switch replacement could be complicated/impractical for IFs nested in both branches (shown with alternatives of indentation, indented on both sides), making full symmetrical tree:

{{#ifeq:{{{1}}}|condition1
 |<!--then-->branch1t{{
  #ifeq:{{{1}}}|condition2
   |<!--then-->branch1t2t{{#ifeq:{{{1}}}|condition4|<!--then-->branch1t2t4t|<!--else-->branch1t2t4e}}
   |<!--else-->branch1t2e{{#ifeq:{{{1}}}|condition5|<!--then-->branch1t2e5t|<!--else-->branch1t2e5e}}
  }}
 |<!--else-->branch1e{{#ifeq:{{{1}}}|condition3
   |<!--then-->branch1e3t{{#ifeq:{{{1}}}|condition6|branch1e3t6t|branch1e3t6e}}
   |<!--else-->branch1e3e{{
    #ifeq:{{{1}}}|condition7
     |branch1e3e7t
     |branch1e3e7t
    }}
  }}
}}

#time

This parser function takes a date and/or time (in the Gregorian calendar) and formats it according to the syntax given. A date/time object can be specified; the default is the value of the magic word {{CURRENTTIMESTAMP}} – that is, the time the page was last rendered into HTML.

{{#time: format string }}
{{#time: format string | date/time object }}
{{#time: format string | date/time object | language code }}
{{#time: format string | date/time object | language code | local }}

The list of accepted formatting codes is given in the table to the right. Any character in the formatting string that is not recognized is passed through unaltered; this applies also to blank spaces (the system does not need them for interpreting the codes). If no character is recognized in the formatting string, and the date/time object is without error, then the formatting string is returned as output. There are also two ways to escape characters within the formatting string:

  1. A backslash followed by a formatting character is interpreted as a single literal character
  1. Characters enclosed in double quotes are considered literal characters, and the quotes are removed.

In addition, the digraph xx is interpreted as a single literal "x".

As the list of formatting codes continues to evolve (with the support of new calendars, or of new date fields computed and formatted differently), you should escape all literal characters (not just ASCII letters currently used by formatting codes) that need to be passed through unaltered.

Unfortunately, for now, the ASCII single quote is still not recognized as a simple alternative for marking literal text to the currently supported ASCII double quotes (for example, double quotes are mandatory for in other uses like the delimitation of string values in JSON, C, C++...) and backslashes (which have to be escaped as well in string constants used by many languages, including JSON, C, C++, PHP, JavaScript, Lua). So you still cannot embed any literal double quote without escaping it with a backslash (or you can use other curly, angular or square quotation marks instead).

{{#time: Y-m-d }}2024-11-04
{{#time: [[Y]] m d }}2024 11 04
{{#time: [[Y (year)]] }}2024 (24UTCpmMon, 04 Nov 2024 14:27:33 +0000)
{{#time: [[Y "(year)"]] }}2024 (year)
{{#time: i's" }}27'33"

The date/time object can be in any format accepted by PHP's strtotime() function. Absolute (e.g. 20 December 2000), relative (e.g. +20 hours), and combined times (e.g. 30 July +1 year) are accepted.

{{#time: r|now}}Mon, 04 Nov 2024 14:27:34 +0000
{{#time: r|+2 hours}}Mon, 04 Nov 2024 16:27:34 +0000
{{#time: r|now + 2 hours}}Mon, 04 Nov 2024 16:27:34 +0000
{{#time: r|20 December 2000}}Wed, 20 Dec 2000 00:00:00 +0000
{{#time: r|December 20, 2000}}Wed, 20 Dec 2000 00:00:00 +0000
{{#time: r|2000-12-20}}Wed, 20 Dec 2000 00:00:00 +0000
{{#time: r|2000 December 20}}Feeler: ongëlteg Zäit

The language code in ISO 639-3 (?) allows the string to be displayed in the chosen language

{{#time:d F Y|1988-02-28|nl}}28 februari 1988
{{#time:l|now|uk}}понеділок
{{#time:d xg Y|20 June 2010|pl}}20 czerwca 2010

The local parameter specifies if the date/time object refers to the local timezone or to UTC.

This is a boolean parameters: its value is determined by casting the value of the argument (see the official PHP documentation for details on how string are cast to boolean values).

Please note that, if the variable $wgLocaltimezone is set to UTC, there is no difference in the output when local is set to true or false.

See the following examples for details:

{{#time: Y F d H:i:s|now|it|0}}2024 novembre 04 14:27:34
{{#time: Y F d H:i:s|now|it|1}}2024 novembre 04 14:27:34
{{#time: Y F d H:i:s|+2 hours||0}}2024 November 04 16:27:34
{{#time: Y F d H:i:s|+2 hours||1}}2024 November 04 16:27:34
{{#time:c|2019-05-16T17:05:43+02:00|it}}2019-05-16T15:05:43+00:00
{{#time:c|2019-05-16T17:05:43+02:00|it|0}}2019-05-16T15:05:43+00:00
{{#time:c|2019-05-16T17:05:43+02:00|it|true}}2019-05-16T15:05:43+00:00

If you've calculated a Unix timestamp, you may use it in date calculations by pre-pending an @ symbol.

{{#time: U | now }}1730730454
{{#time: r | @1730730453 }}Mon, 04 Nov 2024 14:27:33 +0000
Warning Warning:

Without the @ prefix before numeric timestamp values, the result is an error most of the time, or is an unexpected value:

{{#time: r | 1970-01-01 00:16:39 }}Thu, 01 Jan 1970 00:16:39 +0000
{{#time: U | 1970-01-01 00:16:39 }}999
{{#time: r | @999 }}Thu, 01 Jan 1970 00:16:39 +0000 (correct)
{{#time: r | 999 }}Feeler: ongëlteg Zäit (unsupported year format)
{{#time: r | 1970-01-01 00:16:40 }}Thu, 01 Jan 1970 00:16:40 +0000
{{#time: U | 1970-01-01 00:16:40 }}1000
{{#time: r | @1000 }}Thu, 01 Jan 1970 00:16:40 +0000 (correct)
{{#time: r | 1000 }}Tue, 04 Nov 1000 00:00:00 +0000 (interpreted as a year with current month and day of the month)
{{#time: r | 1970-01-01 02:46:39 }}Thu, 01 Jan 1970 02:46:39 +0000
{{#time: U | 1970-01-01 02:46:39 }}9999
{{#time: r | @9999 }}Thu, 01 Jan 1970 02:46:39 +0000 (correct)
{{#time: r | 9999 }}Thu, 04 Nov 9999 00:00:00 +0000 (interpreted as a year with current month and day of the month)
{{#time: r | 1970-01-01 02:46:40 }}Thu, 01 Jan 1970 02:46:40 +0000
{{#time: U | 1970-01-01 02:46:40 }}10000
{{#time: r | @10000 }}Thu, 01 Jan 1970 02:46:40 +0000 (correct)
{{#time: r | 10000 }}Feeler: ongëlteg Zäit (unsupported year format)
Warning Warning:

The range of acceptable input is 1 January 0111 → 31 December 9999. For the years 100 through 110 the output is inconsistent, Y and leap years are like the years 100-110, r, D, l and U are like interpreting these years as 2000-2010.

{{#time: d F Y | 29 Feb 0100 }}01 Mäerz 0100
(correct, no leap year), but
{{#time: r | 29 Feb 0100 }}Mon, 01 Mar 0100 00:00:00 +0000 (wrong, even if 100 is interpreted as 2000, because that is a leap year)
{{#time: d F Y | 15 April 10000 }}Feeler: ongëlteg Zäit
{{#time: r | 10000-4-15 }}Sat, 15 Apr 2000 10:00:00 +0000

Year numbers 0-99 are interpreted as 2000-2069 and 1970-1999, except when written in 4-digit format with leading zeros:

{{#time: d F Y | 1 Jan 6 }}01 Januar 2006
{{#time: d F Y | 1 Jan 06 }}01 Januar 2006
{{#time: d F Y | 1 Jan 006 }}01 Januar 2006
{{#time: d F Y | 1 Jan 0006 }}01 Januar 0006 (4-digit format)

The weekday is supplied for the years 100-110 and from 1753, for the years 111-1752 the r-output shows "Unknown" and the l-output "<>". As a consequence, the r-output is not accepted as input for these years.

Full or partial absolute dates can be specified; the function will "fill in" parts of the date that are not specified using the current values:

{{#time: Y | January 1 }}2024
Warning Warning:

The fill-in feature is not consistent; some parts are filled in using the current values, others are not:

{{#time: Y m d H:i:s | June }}2024 06 04 00:00:00 Gives the start of the day, but the current day of the month and the current year.
{{#time: Y m d H:i:s | 2003 }}2003 11 04 00:00:00 Gives the start of the day, but the current day of the year.

There's exception case of the filled day:

{{#time: Y m d H:i:s | June 2003 }}2003 06 01 00:00:00 Gives the start of the day and the start of the month.

A four-digit number is always interpreted as a year, never as hours and minutes:[1]

{{#time: Y m d H:i:s | 1959 }}1959 11 04 00:00:00

A six-digit number is interpreted as hours, minutes and seconds if possible, but otherwise as an error (not, for instance, a year and month):

{{#time: Y m d H:i:s | 195909 }}2024 11 04 19:59:09 Input is treated as a time rather than a year+month code.
{{#time: Y m d H:i:s | 196009 }}Feeler: ongëlteg Zäit Although 19:60:09 is not a valid time, 196009 is not interpreted as September 1960.

The function performs a certain amount of date mathematics:

{{#time: d F Y | January 0 2008 }}31 Dezember 2007
{{#time: d F | January 32 }}Feeler: ongëlteg Zäit
{{#time: d F | February 29 2008 }}29 Februar
{{#time: d F | February 29 2007 }}01 Mäerz
{{#time:Y-F|now -1 months}}2024-Oktober

The total length of the format strings of the calls of #time is limited to 6000 characters[2].

Time Zone issue

There is a bug in this #time parser function (more specifically in PHP DateTime) that does not allow the passing-in of non-integers as relative time zone offsets. This issue does not apply when using an on-the-hour time zone, such as EDT. For example:

  • {{#time:g:i A | -4 hours }} → 10:27 AM

However, India is on a +5.5 hours time offset from UTC, and thus using its time zone will not normally allow the correct calculation of a relative time zone offset. Here's what happens:

  • {{#time:g:i A | +5.5 hours }} → 2:27 PM

To workaround this issue, simply convert the time into minutes or seconds, like this:

  • {{#time:g:i A | +330 minutes }} → 7:57 PM
  • {{#time:g:i A | +19800 seconds }} → 7:57 PM

(Tim Starling, the developer of this function, provided the exact syntax for this solution.)

#time format like in signatures

Sometimes it is useful to construct a timestamp, which looks like the automatic timestamp generated by signatures in discussions on talk pages. On an English-language wiki, it can be created with:

  • {{#timel:H:i, j xg Y (e)|+330 minutes}} → 19:57, 4 November 2024 (UTC)

#timel

This function is a syntactic shortcut that operates identically to {{#time: ... }} with the local parameter set to true, so it always uses the preferred time zone of the user or the configured time zone of the wiki (as set in $wgLocaltimezone )

Syntax of the function is:

{{#timel: format string }}
{{#timel: format string | date/time object }}
{{#timel: format string | date/time object | language code }}
Please note that, if the variable $wgLocaltimezone is set to UTC, there is no difference in the output when local is set to true or false
Example of the use of #time and #timel parser functions from a server where the timezone is not UTC

For instance, see the following examples:

{{#time:c|now|it}}2024-11-04T14:27:34+00:00
{{#time:c|now|it|0}}2024-11-04T14:27:34+00:00
{{#time:c|now|it|1}}2024-11-04T14:27:34+00:00
{{#timel:c|now|it}}2024-11-04T14:27:34+00:00
Warning Example from https://no.wikipedia.org/wiki/Maldiskusjon:Sommertid
Warning Warning:

Be aware that U for both time and timel will return the same number of seconds since 1970-01-01 00:00:00 UTC on Wikipedias with different timezones than UTC (formerly known as GMT)

U Unix time. Seconds since January 1 1970 00:00:00 GMT.
Z Timezone offset in seconds.
{{#time: U}}1730730453
{{#timel: U}}1730730453
{{#time: Z}}0
{{#timel: Z}}0

#timef

This function formats a date using a standard format for the selected language, as defined in $dateFormats (see task T223772).

{{#timef: date/time object }}
{{#timef: date/time object | format type }}
{{#timef: date/time object | format type | language code }}

The format of the date/time object is the same as for #time. If it is empty, the time when the page was rendered is used.

The format type may be one of:

time
Only the time is shown.
date
Only the date is shown.
both
Both the time and date are shown.
pretty
Only the date is shown, using an abbreviated format which does not include the year. Not all languages support this; if it is not supported, the "date" format is used.

If the format type is not specified, both the time and date will be show, as if both were specified.

If the language code is not specified, the page's content language is used.

Using #timef instead of #time allows templates to more easily support multiple languages, since different languages have different ways to format dates.

In English, the order of the day and month is controlled by $wgAmericanDates .

Examples:

{{#timef:now|both|en}} 14:27, 4 November 2024
{{#timef:now|both|ja}} 2024年11月4日 (月) 14:27
{{#timef:now|pretty|en}} 4 November
{{#timef:now|pretty|pl}} 4 listopada
{{#timef:|time}} 14:27

#timefl

This function is the same as #timef except that it uses the local timezone of the wiki as configured in $wgLocaltimezone .

{{#timefl: date/time object }}
{{#timefl: date/time object | format type }}
{{#timefl: date/time object | format type | language code }}

#titleparts

This function separates a page title into segments based on slashes, then returns some of those segments as output.

{{#titleparts: pagename | number of segments to return | segment to start at }}

If the number of segments to return parameter is not specified, it defaults to "0", which returns all the segments from the segment to start at to the end (included). If the segment to start at parameter is not specified or is "0", it defaults to "1":

{{#titleparts: Talk:Foo/bar/baz/quok }}Talk:Foo/bar/baz/quok
{{#titleparts: Talk:Foo/bar/baz/quok | 1 }}Talk:Foo See also {{ROOTPAGENAME }}.
{{#titleparts: Talk:Foo/bar/baz/quok | 2 }}Talk:Foo/bar
{{#titleparts: Talk:Foo/bar/baz/quok | 2 | 2 }}bar/baz
{{#titleparts: Talk:Foo/bar/baz/quok | 2 | 3 }}baz/quok
{{#titleparts: Talk:Foo/bar/baz/quok | 3 | 2 }}bar/baz/quok
{{#titleparts: Talk:Foo/bar/baz/quok | | 2 }}bar/baz/quok
{{#titleparts: Talk:Foo/bar/baz/quok | | 5 }}

Negative values are accepted for both values. Negative values for the number of segments to return parameter effectively 'strips' segments from the end of the string. Negative values for the first segment to return translates to "start with this segment counting from the right":

{{#titleparts: Talk:Foo/bar/baz/quok | -1 }}Talk:Foo/bar/baz Strips one segment from the end of the string. See also {{BASEPAGENAME}}.
{{#titleparts: Talk:Foo/bar/baz/quok | -4 }} Strips all 4 segments from the end of the string
{{#titleparts: Talk:Foo/bar/baz/quok | -5 }} Strips 5 segments from the end of the string (more than exist)
{{#titleparts: Talk:Foo/bar/baz/quok | | -1 }} quok Returns last segment. See also {{SUBPAGENAME}}.
{{#titleparts: Talk:Foo/bar/baz/quok | -1 | 2 }} bar/baz Strips one segment from the end of the string, then returns the second segment and beyond
{{#titleparts: Talk:Foo/bar/baz/quok | -1 | -2 }} baz Start copying at the second last element; strip one segment from the end of the string

Before processing, the pagename parameter is HTML-decoded: if it contains some standard HTML character entities, they will be converted to plain characters (internally encoded with UTF-8, i.e. the same encoding as in the MediaWiki source page using this parser function).

For example, any occurrence of &quot;, &#34;, or &#x22; in pagename will be replaced by ".
No other conversion from HTML to plain text is performed, so HTML tags are left intact at this initial step even if they are invalid in page titles.

Some magic keywords or parser functions of MediaWiki (such as {{PAGENAME }} and similar) are known to return strings that are needlessly HTML-encoded, even if their own input parameter was not HTML-encoded:

The titleparts parser function can then be used as a workaround, to convert these returned strings so that they can be processed correctly by some other parser functions also taking a page name in parameter (such as {{PAGESINCAT: }}) but which are still not working properly with HTML-encoded input strings.

For example, if the current page is Category:Côte-d'Or, then:

  • {{#ifeq: {{FULLPAGENAME}} | Category:Côte-d'Or | 1 | 0 }}, and {{#ifeq: {{FULLPAGENAME}} | Category:Côte-d&apos;Or | 1 | 0 }} are both returning 1; (the #ifeq parser function does perform the HTML-decoding of its input parameters).
  • {{#switch: {{FULLPAGENAME}} | Category:Côte-d'Or = 1 | #default = 0 }}, and {{#switch: {{FULLPAGENAME}} | Category:Côte-d&apos;Or = 1 | #default = 0 }} are both returning 1; (the #switch parser function does perform the HTML-decoding of its input parameters).
  • {{#ifexist: {{FULLPAGENAME}} | 1 | 0 }}, {{#ifexist: Category:Côte-d'Or | 1 | 0 }}, or even {{#ifexist: Category:Côte-d&apos;Or | 1 | 0 }} will all return 1 if that category page exists (the #ifexist parser function does perform the HTML-decoding of its input parameters);
  • {{PAGESINCAT: Côte-d'Or }} will return a non-zero number, if that category contains pages or subcategories, but:
  • {{PAGESINCAT: {{CURRENTPAGENAME}} }}, may still unconditionally return 0, just like:
  • {{PAGESINCAT: {{PAGENAME:Category:Côte-d'Or}} }}
  • {{PAGESINCAT: {{PAGENAME:Category:Côte-d&apos;Or}} }}

The reason of this unexpected behavior is that, with the current versions of MediaWiki, there are two caveats:

  • {{FULLPAGENAME}}, or even {{FULLPAGENAME:Côte-d'Or}} may return the actually HTML-encoded string Category:Côte-d&apos;Or and not the expected Category:Côte-d'Or, and that:
  • {{PAGESINCAT: Côte-d&apos;Or }} unconditionally returns 0 (the PAGESINCAT magic keyword does not perform any HTML-decoding of its input parameter).

The simple workaround using titleparts (which will continue to work if the two caveats are fixed in a later version of MediaWiki) is:

  • {{PAGESINCAT: {{#titleparts: {{CURRENTPAGENAME}} }} }}
  • {{PAGESINCAT: {{#titleparts: {{PAGENAME:Category:Côte-d'Or}} }} }}
  • {{PAGESINCAT: {{#titleparts: {{PAGENAME:Category:Côte-d&apos;Or}} }} }}, that all return the actual number of pages in the same category.

Then the decoded pagename is canonicalized into a standard page title supported by MediaWiki, as much as possible:

  1. All underscores are automatically replaced with spaces:
    {{#titleparts: Talk:Foo/bah_boo|1|2}}bah boo Not bah_boo, despite the underscore in the original.
  2. The string is split a maximum of 25 times; further slashes are ignored and the 25th element will contain the rest of the string. The string is also limited to 255 characters, as it is treated as a page title:
    {{#titleparts: a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/aa/bb/cc/dd/ee | 1 | 25 }}y/z/aa/bb/cc/dd/ee
    If for whatever reason you needed to push this function to its limit, although very unlikely, it is possible to bypass the 25 split limit by nesting function calls:
    {{#titleparts: {{#titleparts: a/b/c/d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z/aa/bb/cc/dd/ee| 1 | 25 }} | 1 | 2}}z
  3. Finally the first substring is capitalized according to the capitalization settings of the local wiki (if that substring also starts by a local namespace name, that namespace name is also normalized).
    {{#titleparts: talk:a/b/c }}Talk:A/b/c

You can use #titleparts as a small "string parser and converter", but consider that it returns the first substring capitalized:

{{#titleparts: one/two/three/four|1|1 }}One
{{#titleparts: one/two/three/four|1|2 }}two

If lower case is needed, use lc: function to control output:

{{lc: {{#titleparts: one/two/three/four|1|1 }} }}one

You can prepend a 'dummy' slash at the beginning of the string to get the correct first substring capitalization (uppercase or lowercase). Use 2 instead of 1 for first segment to return:

{{#titleparts: /one/two/three/four|1|2 }}one
{{#titleparts: /One/two/three/four|1|2 }}One
Warning Warning:

Certain characters that are illegal in a page title will cause #titleparts to not parse the string:

{{#titleparts: {one/two} | 1 | 1 }}{one/two}. Does not produce the expected: {one
{{#titleparts: [[page]]/123 | 1 | 2 }}page/123. Does not work because brackets are illegal in page titles and this parser function does not process links embedded in its input pagename parameter, even when they use the MediaWiki syntax, or any other HTML or MediaWiki tags.
{{#titleparts: red/#00FF00/blue | 1 | 3 }} → "". Does not work because "#" is also illegal in page titles.
Warning Warning:

If any part of the title is just "." or "..", #titleparts will not parse the string:

{{#titleparts: one/./three | 1 | 1 }}one/./three. The whole string is returned. It does not produce the expected: one
Warning Warning: This function does not degrade gracefully if the input exceeds 255 bytes in UTF-8. If the input string is 256 bytes or more, the whole string is returned.

String functions

The ParserFunctions extension optionally defines various string functions if $wgPFEnableStringFunctions is set to true:

  • #len
  • #pos
  • #rpos
  • #sub
  • #count
  • #replace
  • #explode
  • #urldecode

See the dedicated subpage for documentation, and Manual:Performing string operations with parser functions for examples.

Warning Warning: In 2013, it was decided that these functions will never be enabled on any Wikimedia wiki, because they are inefficient when used on a large scale (see phab:T8455 for some history). These functions do NOT work on Wikimedia wikis!

If you are here to write something on a Wikimedia project, you are looking for something else: if your home wiki has string functions, it probably uses Lua . For example, the English Wikipedia uses Module:String, which does some of the same things with wildly different syntax. There are also individual String-handling templates.

Here is a short overview of Module:String functions:

  • #len (length of string): {{#invoke:String|len|target_string}}
  • #sub (substring): {{#invoke:String|sub|target_string|start_index|end_index}}
  • #match: {{#invoke:String|match|source_string|pattern_string|start_index|match_number|plain_flag|nomatch_output}}
  • #pos (position of target): {{#invoke:String|pos|target_string|index_value}}
  • #find: {{#invoke:String|find|source_string|target_string|start_index|plain_flag}}
  • #replace: {{#invoke:String|replace|source_str|pattern_string|replace_string|replacement_count|plain_flag}}
  • #rep (repeat): {{#invoke:String|rep|source|count}}
  • #escapePattern: {{#invoke:String|escapePattern|pattern_string}}
  • #count: {{#invoke:String|count|source_str|pattern_string|plain_flag}}
  • #join: {{#invoke:String|join|separator|string1|string2|...}}

General points

Substitution

Parser functions can be substituted by prefixing the hash character with subst::

{{subst:#ifexist: Help:Extension:ParserFunctions/lb | [[Help:Extension:ParserFunctions/lb]] | Help:Extension:ParserFunctions/lb }}the code [[Help:Extension:ParserFunctions/lb]] will be inserted in the wikitext since the page Help:Extension:ParserFunctions/lb exists.
Warning Warning:

The results of substituted parser functions are undefined if the expressions contain unsubstituted volatile code such as variables or other parser functions. For consistent results, all the volatile code in the expression to be evaluated must be substituted. See Help:Substitution.

Substitution does not work within ‎<ref>‎</ref> ; you can use {{subst:#tag:ref|}} for this purpose.

Redirects

Especially {{#time:…|now-…}} could be handy in redirects to pages including dates, but this does not work.

Escaping pipe characters in tables

Parser functions will mangle wikitable syntax and pipe characters (|), treating all the raw pipe characters as parameter dividers. To avoid this, most wikis used a template Template:! with its contents only a raw pipe character (|), since MW 1.24 a {{!}} magic word replaced this kludge. This 'hides' the pipe from the MediaWiki parser, ensuring that it is not considered until after all the templates and variables on a page have been expanded. It will then be interpreted as a table row or column separator. Alternatively, raw HTML table syntax can be used, although this is less intuitive and more error-prone.

You can also escape the pipe character for display as a plain, uninterpreted character using an HTML entity: &#124; .

Description You type You get
Escaping pipe character as table row/column separator
{{!}}
|
Escaping pipe character as a plain character
&#124;
|

Stripping whitespace

Whitespace, including newlines, tabs, and spaces, is stripped from the beginning and end of all the parameters of these parser functions. If this is not desirable, comparison of strings can be done after putting them in quotation marks.

{{#ifeq: foo           |           foo | equal | not equal }}equal
{{#ifeq: "foo          " | "          foo" | equal | not equal }}not equal

To prevent the trimming of then and else parts, see m:Template:If. Some people achieve this by using <nowiki > </nowiki> instead of spaces.

foo{{#if:|| bar }}foofoobarfoo
foo{{#if:||<nowiki /> bar <nowiki />}}foofoo bar foo

However, this method can be used to render a single whitespace character only, since the parser squeezes multiple whitespace characters in a row into one.

<span style="white-space: pre;">foo{{#if:||<nowiki/>      bar      <nowiki/>}}foo</span>
foo bar foo

In this example, the white-space: pre style is used to force the whitespace to be preserved by the browser, but even with it the spaces are not shown. This happens because the spaces are stripped by the software, before being sent to the browser.

It is possible to workaround this behavior replacing whitespaces with &#32; (breakable space) or &nbsp; (non-breakable space), since they are not modified by the software:

<span style="white-space: pre;">foo{{#if:||&#32;&#32;&#32;bar&#32;&#32;&#32;}}foo</span>foo bar foo
foo{{#if:||&nbsp;&nbsp;&nbsp;bar&nbsp;&nbsp;&nbsp;}}foofoo   bar   foo

Beware that not all parameters are created equal. In ParserFunctions, whitespace at the beginning and end is always stripped. In templates , whitespace at the beginning and end is stripped for named parameters and named unnamed parameters but not from unnamed parameters:

foo{{1x|content= bar}}foofoobarfoo
foo{{1x|1= bar}}foofoobarfoo
foo{{1x| bar }}foofoo bar foo

Other parser functions

Case conversion functions

  • Lowercase: "{{lc: AbC}}" → "abc" [1]
  • Uppercase: "{{uc: AbC}}" → "ABC" [2]
  • Lowercase first character: "{{lcfirst: AbC}}" → "abC" [3]
  • Uppercase first character: "{{ucfirst: abc}}" → "Abc" [4]

Encoding functions

  • URL encoding:
"{{urlencode: AbC
dEf ghi}}"

renders as


"AbC%0AdEf+ghi"


So inner new lines convert into %0A, and inner spaces convert into +.

Anchor encoding

{{anchorencode: AbC dEf ghi}}

renders as


AbC_dEf_ghi


Padding functions

  • "{{padleft: bc d |8|a}}" gives "aaaabc d" [5]
  • "{{padright: bc d |8|a}}" gives "bc daaaa" [6]

Formatting functions

  • "{{formatnum: 1234567890}}" gives "1.234.567.890" [7]

See also

References

  1. Prior to r86805 in 2011 this was not the case.
  2. ParserFunctions.php at phabricator.wikimedia.org