Manual:Parser functions/da

Parserfunktioner, som tilføjedes i MediaWiki version 1.7, er en type udvidelse, der er tæt knyttet til syntaks-analysen, også kaldet parseren. Udtrykket "parserfunktion" må ikke forveksles med Extension:ParserFunctions, som er en samling af simple parserfunktioner.

Beskrivelse
Mærkeudvidelser er bygget til at omdanne uforarbejdet tekst til HTML og har meget lidt til fælles med resten af syntaksanalysen. For eksempel kan resultatet fra en mærkeudvidelse ikke anvendes som skabelon-parameter. Desuden er det muligt at bygge skabeloner ind i en mærkeudvidelse, men det skal gøres manuelt og kan være en fejlbehæftet proces, der skifter fra version til version.

Den typiske syntaks for en parserfunktion er:

Oprettelse af en parserfunktion er lidt mere kompliceret end at skabe et nyt mærke, fordi funktionens navn skal være et magisk ord/da - et nøgleord, der understøtter aliaser og sprogversioner.

Simpelt eksempel
Nedenfor er et eksempel på en udvidelse, der skaber en parserfunktion.

Denne fil skal kaldes ExampleExtension.php, hvis navnet på din udvidelse er ExampleExtension:

En anden fil, ExtensionName.i18n.php, bør indeholde:

Med denne udvidelse aktiveret producerer



resultatet:


 * param1 is hello and param2 is hi

Bemærk: Denne magicWords tabel er ikke valgfri. Hvis den udelades, vil parserfunktionen simpelthen ikke virke og vil blive gengivet som om udvidelsen ikke er blevet installeret.

Længere funktioner
For longer functions, you may want to split the hook functions out to a _body.php or .hooks.php file and make them static functions of a class. Then you can load the class with $wgAutoloadClasses and call the static functions in the hooks, e.g.:

Put this in your  file:

Then put this is in your  file:

Caching
As with tag extensions, $parser->disableCache may be used to disable the cache for dynamic extensions.

Controlling the parsing of output
To have the wikitext returned by your parser function be fully parsed (including expansion of templates), set the noparse option to false when returning: It seems the default value for noparse changed from false to true, at least in some situations, sometime around version 1.12.

Conversely, to have your parser function return HTML that remains unparsed, rather than returning wikitext, use this:

However, This is a test. will produce something like this:

This is

param1 is hello and param2 is hi a test.

This happens due to a hardcoded "\n\n" that is prepended to the HTML output of parser functions. To avoid that and make sure the HTML code is rendered inline to the surrounding text, you can use this:

Naming
By default, MW adds a hash character (number sign, "#") to the name of each parser function. To suppress that addition (and obtain a parser function with no "#" prefix), include the SFH_NO_HASH constant in the optional flags argument to setFunctionHook, as described below.

When choosing a name without a hash prefix, note that transclusion of a page with a name starting with that function name followed by a colon is no longer possible. In particular, avoid function names equal to a namespace name. In the case that interwiki transclusion is enabled, also avoid function names equal to an interwiki prefix.

The setFunctionHook hook
For more details of the interface into the parser, see the documentation for setFunctionHook in includes/Parser.php. Here's a (possibly dated) copy of those comments:

function setFunctionHook( $id, $callback, $flags = 0 )

Parameters:


 * string $id - The magic word ID
 * mixed $callback - The callback function (and object) to use
 * integer $flags - Optional, set it to the SFH_NO_HASH constant to call the function without "#".

Return value: The old callback function for this name, if any

Create a function, e.g.,. The callback function should have the form:

The callback may either return the text result of the function, or an array with the text in element 0, and a number of flags in the other elements. The names of the flags are specified in the keys. Valid flags are:


 * found : The text returned is valid, stop processing the template. This is on by default.
 * nowiki : Wiki markup in the return value should be escaped
 * noparse : Unsafe HTML tags should not be stripped, etc.
 * noargs : Don't replace triple-brace arguments in the return value
 * isHTML : The returned text is HTML, armour it against wikitext transformation

Named parameters
Parser functions do not support named parameters the way templates and tag extensions do, but it is occasionally useful to fake it. Users are often accustomed to using vertical bars ( | ) to separate arguments, so it's nice to be able to do that in the parser function context, too. Here's a simple example of how to accomplish this.

Your callback function typically looks like this:

To fake named parameters, simply omit all the arguments after, and pair it with. Here is an example: