Ajuda:Extensão:Funções do Analisador

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A extensão ParserFunctions fornece onze funções do analisador adicionais para complementar as "palavras mágicas ", que já estão presentes no MediaWiki. (a extensão pode ser configurada para fornecer funções adicionais para o tratamento de texto; estas funções de texto estão documentadas noutra página ). Todas as funções fornecidas pela extensão têm a forma:

{{#nome da função: argumento 1 | argumento 2 | argumento 3 ... }}
PD Nota: Quando modificais esta página, estais a aceitar que a vossa contribuição se publique no marco de CC0. Olhem Páginas de ajuda de domínio público para mais informação. PD

#expr

Tipo Operadores
Agrupamento (parênteses) ( )
Números 1234.5   e (2.718)   pi (3.142)
operador binário e   unário +,-
Unários not ceil trunc floor abs exp ln sin cos tan acos asin atan
Binários ^
* / div mod
+ -
Arredondamento round
Lógicos = != <> > < >= <=
and
or

Esta função calcula uma expressão matemática e devolve o valor calculado. A função também está disponível no Extensão:Scribunto através da função mw.ext.ParserFunctions.expr.

{{#expr: expressão }}

Basic example

{{#expr: 1 + 1 }}2

Os operadores disponíveis estão listados na tabela da direita, por ordem crescente de precedência. Consulte Help:Cálculos para mais detalhes sobre a função de cada operador. A exactidão e o formato do resultado devolvido dependem do sistema operativo do servidor que está a executar o MediaWiki, e do formato numérico da língua do site.

Quando avaliar utilizando a álgebra booliano, o número zero assume o valor "false" e qualquer valor diferente de zero, positivo ou negativo, assume o valor "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

Uma expressão de entrada vazia devolve um texto vazio. Expressões inválidas devolvem uma das várias mensagens de erro, que podem ser apanhadas usando a função #iferror:

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

A ordem dos operandos de adição e subtracção antes ou depois de um número é significativa, e pode ser tratada como um valor positivo ou negativo em vez de como um operando com uma entrada errada:

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

Note que, ao usar o resultado de palavras mágicas, tem de formatá-las para remover vírgulas e traduzir os números. Por exemplo, $numberofusers resulta em $nou-result, quando desejamos $nou-result-raw, que pode ser obtido por $numberofusers2. Isto é especialmente importante nalgumas línguas em que os números são traduzidos. Por exemplo, na língua Bengali, $numberofusers3 produz $bengali. For example, {{NUMBEROFUSERS}} results in 17 908 471, where we want 17908471, 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}} Expression error: Unrecognized punctuation character " ".
{{#expr:{{formatnum:{{NUMBEROFUSERS}}|R}}+100}}17908571
Aviso Aviso: O operador mod produz resultados incorretos para alguns valores do segundo argumento:
{{#expr: 123 mod (2^64-1)}}Division by zero. (produz um texto vazio; devia produzir 123)
Se pretende efetuar cálculos com base em datas (por exemplo, determinar se a data e a hora atuais são posteriores a outra data e hora), primeiro converta a hora para o número de segundos após 1 de janeiro de 1970 usando {{#time: xNU }}, e depois pode simplesmente somar e subtrair datas como números.

Arredondamento

Arredonda o número à sua esquerda para um múltiplo de 1/10 elevado a uma potência, com o expoente igual ao valor truncado do número à direita.

Para arredondar por excesso ou por defeito, use os operadores unários ceil ou floor respetivamente.

Caso de teste Resultado Método de arredondamento
{{#expr: 1/3 round 5 }} 0.33333 O algarismo final é < 5, não ocorre nenhum arredondamento aparente (0.333333… → 0.33333)
{{#expr: 1/6 round 5 }} 0.16667 O algarismo final é ≥ 5, portanto é arredondado por excesso (0.166666… → 0.16667)
{{#expr: 8.99999/9 round 5 }} 1 Novamente, o resultado é arredondado por excesso no último algarismo, o que resulta num arredondamento adicional (0.999998… → 1.00000 → 1)
{{#expr: 1234.5678 round -2 }} 1200 Arredondado para a centena mais próxima porque valores negativos arredondam à esquerda da vírgula decimal
{{#expr: 1234.5678 round 2 }} 1234.57 Arredondado para a centésima mais próxima porque valores positivos arredondam à direita da vírgula decimal
{{#expr: 1234.5678 round 2.3 }} 1234.57 Decimais no índice de arredondamento não fazem diferença no resultado arredondado
{{#expr: trunc 1234.5678 }} 1234 Parte decimal truncada (cortada)
Arredondamento para o número inteiro mais próximo
{{#expr: 1/3 round 0 }} 0 Por defeito para o inteiro mais próximo, que é zero
{{#expr: 1/2 round 0 }} 1 Por excesso para o inteiro mais próximo, que é um
{{#expr: 3/4 round 0 }} 1 Por excesso para o inteiro mais próximo, que é um
{{#expr: -1/3 round 0 }} -0 Por excesso para o inteiro mais próximo, que é zero
{{#expr: -1/2 round 0 }} -1 Por defeito para o inteiro mais próximo, que é o menos um
{{#expr: -3/4 round 0 }} -1 Por defeito para o inteiro mais próximo, que é o menos um
Arredondamento por excesso ou defeito com ceil e floor
{{#expr: ceil(1/3) }} 1 Por excesso para o inteiro mais próximo maior, que é um
{{#expr: floor(1/3) }} 0 Por defeito para o inteiro mais próximo menor, que é zero
{{#expr: ceil(-1/3) }} -0 Por excesso para o inteiro mais próximo maior, que é zero
{{#expr: floor(-1/3) }} -1 Por defeito para o inteiro mais próximo menor, que é o menos um
{{#expr: ceil 1/3 }} 0.33333333333333 Não arredondado, uma vez que 1 já é um inteiro
Aviso Aviso: Interpretado como (ceil 1)/3, e não ceil(1/3), como seria de esperar

Textos

As expressões só funcionam com valores semelhantes a números, não podem comparar textos (strings) nem caracteres. Em alternativa, pode usar-se #ifeq.

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

#if

Esta função determina se um texto de teste tem conteúdo ou está vazio. Um texto de teste que só contém caracteres em branco (espaços, linhas novas, etc.) é considerado vazio.

{{#if: texto de teste | valor se o texto de teste não está vazio | valor se o texto de teste está vazio (ou só contém caracteres em branco)}}
{{#if: primeiro parâmetro | segundo parâmetro | terceiro parâmetro }}

Esta função testa se o primeiro parâmetro não está vazio. Se o primeiro parâmetro não estiver vazio a função apresenta o segundo argumento. Se o primeiro parâmetro estiver vazio ou contiver apenas caracteres em branco (espaços, linhas novas, etc.) ela apresenta o terceiro argumento.

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

O texto de teste é sempre interpretado como texto puro, portanto expressões matemáticas não são avaliadas:

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

O último parâmetro (falso) pode ser omitido:

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

A função pode ser intercalada. Para fazê-lo, coloque a função #if interior na sua forma integral, no lugar de um parâmetro da função #if exterior. É possível intercalar até uma profundidade de sete níveis, embora isto possa depender da wiki ou de um limite de memória.

{{#if:texto de teste
|valor se o texto de teste não está vazio
|{{#if:test string
  |value if test string is not empty
  |valor se o texto de teste está vazio (ou só contém caracteres em branco)
  }}
}}

value if test string is not empty

Também pode usar um parâmetro como texto de teste na sua declaração #if. Tem de se certificar que adicionou a | (barra vertical) após o nome da variável. (Assim, se o parâmetro não tiver um valor, ele será avaliado como um texto vazio em vez do texto "{{{1}}}".)

{{#if:{{{1|}}}|Colocou texto na variável 1|Não há texto na variável 1}}

Consulte Help:Parâmetros de funções nas predefinições para mais exemplos desta função.

#ifeq

Esta função do analisador compara dois textos, determina se são ou não idênticos, e devolve um dos dois textos com base no resultado. Se mais comparações e sequências de saída forem necessárias, considere utilizar #switch.

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

Se ambos os textos são valores numéricos válidos, os textos são comparados numericamente:

{{#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

Caso contrário, a comparação é feita como texto; esta comparação é sensível ao uso de maiúsculas e minúsculas:

{{#ifeq: foo | bar | equal | not equal}}not equal
{{#ifeq: foo | Foo | equal | not equal}}not equal
{{#ifeq: "01" | "1" | equal | not equal}}not equal  (comparar com o exemplo semelhante acima, sem as aspas)
{{#ifeq: 10^3 | 1000 | equal | not equal}}not equal  (comparar com o exemplo semelhante acima, com #expr a devolver primeiro um número válido)

Como um exemplo prático, considere um modelo existente Template:Temporizador utilizado o analisador para escolher dois tempos padrão, curto e longo. Este utiliza o parâmetro como a primeira entrada para comparar com o texto "curto", não há convenção para a ordem, mas é mais simples ler se o parâmetro for o primeiro. O código do modelo é definido como:

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

acontecerá o seguinte:

{{timer|short}}20
{{timer|20}}40
{{timer}}40
Aviso Aviso: Quando usadas dentro de uma função do analisador sintático, quaisquer etiquetas do analisador e as outras funções do analisador sintático têm de ser temporariamente substituídas por um código único . Isto afeta as comparações:
{{#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
Se os dois textos que são comparados forem chamadas idênticas para uma mesma predefinição que contenha essas etiquetas, então o resultado é verdadeiro, mas se forem chamadas para duas predefinições distintas com conteúdo idêntico que contenham essas etiquetas, o resultado é falso.
Aviso Aviso: As comparações literais com palavras mágicas sobre nomes de páginas podem falhar dependendo da configuração do site. Por exemplo, {{FULLPAGENAME}}, dependendo da wiki, pode converter a primeira letra para maiúsculas, e irá substituir todos os espaços sublinhados com espaços.

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

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

#iferror

Esta função recebe um texto de entrada e devolve um de dois resultados; resulta no valor true se o texto de entrada contém um objeto HTML com class="error", tal como é gerado por outras funções do analisador sintático como #expr, #time e #rel2abs, erros em predefinições como ciclos e recursividade, e outros erros do analisador sintático em modo de capacidade diminuída.

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

Podem ser omitidos um ou ambos os textos a devolver. Se o texto para correto for omitido, é devolvido o texto de teste se este não estiver errado. Se o texto para erro também for omitido, será devolvido um texto vazio em caso de erro:

{{#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

Esta função avalia uma expressão matemática e devolve um de dois textos, dependendo do valor booleano do resultado:

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

A expressão de entrada é avaliada exatamente como para #expr acima, estando disponíveis os mesmos operadores. A saída é então avaliada como uma expressão booleana.

Uma expressão de entrada vazia é avaliada como false:

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

Como mencionado acima, zero é avaliado como false e qualquer valor diferente de zero é avaliado como true, portanto esta função é equivalente a uma que use apenas #ifeq e #expr:

{{#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.

comparação

{{#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
Aviso Aviso: Os resultados de comparações numéricas com #ifexpr nem sempre são compatíveis com #ifeq e #switch. Estes dois últimos são mais precisos que #ifexpr, e não devolvem resultados equivalentes.

Considere estas comparações com o dígito final alterado:

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

Porque PHP utilizado em #ifeq e #switch compara dois números do tipo inteiro, este devolve o resultado esperado corretamente. Considerando que com #ifexpr e os mesmos números:

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

Com o dígito diferente, o resultado de igual está realmente incorreto.

Este comportamento no #ifexpr é causado porque o MediaWiki converte números literais em expressões no tipo float que, para os números inteiros grandes como estes, envolve arredondamentos.

#ifexist

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/pt | exists | doesn't exist }}exists
{{#ifexist: XXHelp:Extension:ParserFunctions/ptXX | 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 (porque a extensão Checkuser está instalada nesta wiki)
{{#ifexist: MediaWiki:Copyright | exists | doesn't exist }}exists (porque MediaWiki:Copyright foi personalizado)

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/pt), Special:WhatLinksHere/Foo will list Help:Extension:ParserFunctions/pt.

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: does not work with interwiki links.

limites de ifexist

#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.

páginas de ifexist e desejadas

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 }}Error: Invalid depth in path: "Help:Foo/bar/baz/../../../../quok" (tried to access a node above the root node).

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
}}

Exemplos:

{{#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.

Predefinição

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 }}

Agrupar resultados

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:Parâmetros de funções nas predefinições .)

{{#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|}}}).

Comportamento de comparação

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
Aviso Aviso:

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;.

Exemplo:

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 Modelo:Extensão and w:Template:BOTREQ.

Substituir #ifeq

#switch can be used to reduce expansion depth.

Por exemplo:

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

é equivalente a

  • {{#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). 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 }}2024-03-19
{{#time: [[Y]] m d }}2024 03 19
{{#time: [[Y (year)]] }}2024 (24UTCamTue, 19 Mar 2024 03:57:40 +0000)
{{#time: [[Y "(year)"]] }}2024 (year)
{{#time: i's" }}57'40"

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}}Tue, 19 Mar 2024 03:57:40 +0000
{{#time: r|+2 hours}}Tue, 19 Mar 2024 05:57:40 +0000
{{#time: r|now + 2 hours}}Tue, 19 Mar 2024 05:57:40 +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}}Error: Invalid time.

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}}вівторок
{{#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 marzo 19 03:57:40
{{#time: Y F d H:i:s|now|it|1}}2024 marzo 19 03:57:40
{{#time: Y F d H:i:s|+2 hours||0}}2024 março 19 05:57:40
{{#time: Y F d H:i:s|+2 hours||1}}2024 março 19 05:57:40
{{#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 }}1710820660
{{#time: r | @1710820660 }}Tue, 19 Mar 2024 03:57:40 +0000
Aviso Aviso:

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 (correto)
{{#time: r | 999 }}Error: Invalid time. (formato de ano não suportado)
{{#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 (correto)
{{#time: r | 1000 }}Wed, 19 Mar 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 (correto)
{{#time: r | 9999 }}Fri, 19 Mar 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 (correto)
{{#time: r | 10000 }}Error: Invalid time. (formato de ano não suportado)
Aviso Aviso:

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 março 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 }}Error: Invalid time.
{{#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 janeiro 2006
{{#time: d F Y | 1 Jan 06 }}01 janeiro 2006
{{#time: d F Y | 1 Jan 006 }}01 janeiro 2006
{{#time: d F Y | 1 Jan 0006 }}01 janeiro 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
Aviso Aviso:

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 19 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 03 19 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 03 19 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 03 19 19:59:09 Input is treated as a time rather than a year+month code.
{{#time: Y m d H:i:s | 196009 }}Error: Invalid time. 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 dezembro 2007
{{#time: d F | January 32 }}Error: Invalid time.
{{#time: d F | February 29 2008 }}29 fevereiro
{{#time: d F | February 29 2007 }}01 março
{{#time:Y-F|now -1 months}}2024-fevereiro

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

Problema da Zona Horária

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 }} → 11:57 PM

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 }} → 3:57 AM

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

  • {{#time:g:i A | +330 minutes }} → 9:27 AM
  • {{#time:g:i A | +19800 seconds }} → 9:27 AM

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

#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}}2024-03-19T03:57:40+00:00
{{#time:c|now|it|0}}2024-03-19T03:57:40+00:00
{{#time:c|now|it|1}}2024-03-19T03:57:40+00:00
{{#timel:c|now|it}}2024-03-19T03:57:40+00:00
Warning Example from https://no.wikipedia.org/wiki/Maldiskusjon:Sommertid
Aviso Aviso:

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}}1710820660
{{#timel: U}}1710820660
{{#time: Z}}0
{{#timel: Z}}0

#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. Consulte também {{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. Consulte também {{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
Aviso Aviso:

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

{{#titleparts: {one/two} | 1 | 1 }}{one/two}. Não produz o esperado: {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.
Aviso Aviso:

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
Aviso Aviso: 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 (#len, #pos, #rpos, #sub, #count, #replace, #explode, #urldecode) if $wgPFEnableStringFunctions is set to true.

Aviso Aviso: 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.

See here for examples.

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|...}}


Pontos gerais

Substituição

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

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

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.

Redireciona

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; .

Descrição Digita Obtém
Escaping pipe character as table row/column separator
{{!}}
|
Escaping pipe character as a plain character
&#124;
|

Remoção de espaço vazio

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

Consulte também

Referências

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