Extensão: Loops

**Manual de extensões do MediaWiki**
Loops; Estado de lançamento: estável
Implementação	Função do analisador
Descrição	Fornece funções do analisador para executar loops
Autor(es)	David M. Sledge; Daniel Werner;
Responsável(eis)	MGChecker
Última versão	0.5.2 (2019-08-05)
MediaWiki	1.34+
PHP	5.6+
Alterações à base de dados	Não
	Parâmetros $wgLoopsEnabledFunctions; $wgLoopsCountLimit;
	Hooks utilizados ParserClearState; ParserFirstCallInit; ParserLimitReportPrepare;
Licence	GNU - Licença Pública Geral 2.0 ou superior
Transferência	Transferir extensão ; Git [?]: Explorar repositório (GitHub); Revisão de código Gerrit; Registo de implementação do Git; Transferir 'tarball' fonte; ; README; RELEASE-NOTES
Exemplo	sandbox.semantic-mediawiki.org
	Traduza a extensão Loops se esta estiver disponível em translatewiki.net
Problemas	Tarefas em aberto · Reportar um erro

This page is a translated version of the page Extension:Loops and the translation is 28% complete.

A extensão Loops fornece Funções de analisador para executar loops.

Currently, this extension is maintained on a basic level by MGChecker.

Utilização

The following examples use the Variables extension and in some cases also the ParserFunctions extension.

`#while`

{{#while}} performs a loop (i.e. it repeatedly parses a given wiki markup block statement) so long as the condition mark-up evaluates to non-whitespace.

{{#while:
 | <condition text>
 | <block statement>
}}

Exemplos

The wiki markup:

{{#vardefine: i | 0 }}{{#while:
 | {{#ifexpr: {{#var: i }} < 5 | true }}
 | <nowiki />
* {{#var: i }}{{#vardefine: i | {{#expr: {{#var: i }} + 1 }} }}
}}

produces the following:

0
1
2
3
4

{{#while}} can also be used in a template to simulate a numbered array. If the page "Template:Loops Test" contains

{{#vardefine: i | 0 }}{{#while:
 | {{{arg{{#var: i }} |}}}
 | <nowiki />
* {{{arg{{#var: i }} }}}{{#vardefine: i
   | {{#expr: {{#var: i }} + 1 }}
 }}
}}

then the wiki-markup

{{Loops Test
 |arg0=Zero
 |arg1=um
 |arg2=dois
 |arg3=três
 |arg4=quatro
}}

produz

zero
um
dois
três
quatro

It's important to note that whitespace, including newlines, tabs, and spaces, is stripped from the beginning and end of all the arguments of these parser functions. If this is not desirable, adding any non-whitespace characters (including the HTML encoding for a whitespace character  ) will prevent further stripping (hence the ‎<nowiki> tags in the above examples).

`#dowhile`

{{#dowhile}} performs exactly like {{#while}}, with the exception that the block statement is guaranteed to be parsed and displayed (if it results in displayable text) at least once. This is done before the condition text is evaluated.

`#loop`

{{#loop: <variable name>
 | <starting value>
 | <number of loops to be performed>
 | <wiki markup>
}}

{{#loop}} repeatedly parses and displays <wiki markup> a number of times equal to the absolute value of <number of loops to be performed>. <Starting value> is placed in a variable (accessible by Variables extension's {{#var:}} parser function) using the name <variable name>. After each loop, the variable is incremented by one if <number of loops to be performed> is positive, or decremented by one if <number of loops to be performed> is negative.

From all loop functions, #loop should have the best performance since there is no condition which has to be expanded and validated for each cycle.

Exemplos

O código seguinte:

{{#loop: varname
 | 4
 | 4
 | <nowiki />
* This is round {{#var: varname }} and we have {{#expr: 7 - {{#var: varname }} }} more to go
}}

produz

This is round 4 and we have 3 more to go
This is round 5 and we have 2 more to go
This is round 6 and we have 1 more to go
This is round 7 and we have 0 more to go

`#forargs` (experimental)

{{#forargs}} é utilizado nos modelos.

It takes arguments that are passed to the template and puts them in variables accessible by Variables extension's {{#var:}} parser function.

{{#forargs: <prefix>
 | <key>
 | <value>
 | <block statement>
}}

This function iterates through each argument whose name begins with <prefix>.

With each iteration it puts the argument name minus <prefix> into <key> as if calling {{#vardefine: <key> }}.

It then takes the value of the argument and puts it into <value> in a similar method.

The block statement is then expanded.

The block statement may contain {{#var: <key> }} and {{#var: <value> }} to access the stored arguments.

Example

If the page "Template:Loops Test" contains

{{#forargs: arg
 | key
 | value
 | <nowiki />
* {{#var: key }} = {{#var: value }}
}}

then the wiki markup

{{Loops Test
 | arg1=val1
 | spam=spammity
 | arg5=val5
 | argument=value
}}

produces

1 = val1
5 = val5
ument = value

`#fornumargs` (experimental)

{{#fornumargs: <key>
 | <value>
 | <block statement>
}}

{{#fornumargs}} performs similarly to {{#forargs}} with two major differences: It doesn't take a prefix argument, and it only works on numbered arguments whether they're explicitly numbered,

{{Template
 | 1=one
 | 2=two
}}

or implicitly numbered.

{{Template
 | one
 | two
}}

Mixing these methods in a single template call may cause values to get overwritten, so be careful.

Examples

If "Template:Loops Test" is edited to contain:

{{#fornumargs: number
 | value
 | <nowiki />
* {{#var: number }} = {{#var: value }}
}}

then

{{Loops Test
  | Apricot
  | B = Bolognese
  | Caramel slice
  | 5 = Eclair
}}

will result in

1 = Apricot
2 = Caramel slice
5 = Eclair

Installation

Some of the parser functions provided by this extension require the ParserFunctions as well as the Variables extension to be installed first.

Exporte e coloque o ficheiro, ou ficheiros, num diretório chamado Loops, na sua pasta extensions/.
Developers and code contributors should install the extension from Git instead, using:
```
cd extensions/
git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/Loops
```
Acrescente o seguinte código ao fundo do ficheiro $LocalSettings:
```
wfLoadExtension( 'Loops' );
```
Configure at your convenience
Pronto – Na página especial Special:Version da sua wiki verifique se a extensão foi instalada.

Configuration

Aviso: Don't edit LocalSettings.php with document editors like Notepad on Windows 10 Version 1809 or earlier, TextEdit, or other text editors that add byte order marks to files. These break the PHP runtime of your wiki. Instead, use a code editor, e.g. Vim or Notepad++. These handle file encodings properly. They can also be used to repair files previously broken by document editors.

These configuration variables have to be set in the LocalSettings.php file after the inclusion of this extension.

$egLoopsCountLimit: This parameter sets the maximum number of loops a page is allowed to perform (default 100). Setting it to -1 lets the loops run within the limits of phps environment. This parameter affects neither the {{#forargs:}} nor {{#fornumargs:}} parser functions.

$egLoopsEnabledFunctions: Configuration variable (array) to define which Loops functions should be enabled. By default, all functions are enabled if the Variables extension is installed as well. If the Variables extension is not installed, #loop, #forargs and #fornumargs will be disabled since they do not work without it being installed. To enable the #fornumargs and #forargs functions only, one can use:

$egLoopsEnabledFunctions = array_diff(
    $egLoopsEnabledFunctions, [
        'forargs', 'fornumargs'
        ]
    );

Utilização

#while

#dowhile

#loop

#forargs (experimental)

#fornumargs (experimental)