Page Text Variables in Pm Wiki at phsne.org/archive

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Defining page text variables
Usage

Page Text Variables were introduced in 2.2.0 beta 2. These are string variables automatically made available through natural page markup or explicitly with page directive markup within the wiki text of the page.

Defining Page Text Variables

There are three ways to define automated Page Text Variables:

use a definition list - the normal pmwiki markup for a definition list will create a page text variable

Example definition list:
:Name: Crisses "{$:Name}"	Name Crisses "Crisses"

This creates a new variable that can be accessed by {$:Name} (becomes: "Crisses") in the page.

use a simple colon delimiter in normal text

Example colon delimited:
Address: 1313 Mockingbird Lane "{$:Address}"	Address: 1313 Mockingbird Lane "1313 Mockingbird Lane"

This creates the {$:Address} variable (variable markup becomes: "1313 Mockingbird Lane") in the page.

hidden directive form - PmWiki markup that doesn't render on the page, but defines the variable

Example directive:
(:Country: Transylvania :) "{$:Country}"	"Transylvania "

This creates the {$:Country} variable (variable markup becomes: "Transylvania ") in the page.

Usage

Usage on the same page

On the same page you can resolve page text variables through the {$:Var} format (shown above).

Usage in headers and footers

If you want a GroupHeader, GroupFooter, SideBar, etc to call on page text variable in the main page, you need to include reference information. To explicitly reference the page text variable from the page being displayed add an asterisk to the page text variable's markup: {*$:Address} on the GroupFooter or GroupHeader page.

Example
{*$:City}	Addis Ababa

To include a page text variable from a header or footer see usage from other pages below.

Usage from other pages

If you want to pull the data from another page, use the {Group/PageName$:Var} format.

Example:
Suburb: Khandallah (:Lake:Taupo:) :Mountain:Mt Ruapehu ->"{PmWiki/PageTextVariables$:Suburb}" ->"{{$FullName}$:Lake}" ->"{PmWiki/PageTextVariables$:Mountain}"	Suburb: Khandallah Mountain Mt Ruapehu "Khandallah" "Taupo" "Mt Ruapehu"

Usage from included pages

Page text variables are never included from their source page. See Usage from other pages above to refer to a page text variable on another page.

Nested page text variables

Page text variables can be nested

Example:
: MailingAddress : {$:Address}, {$:City}, {$:Country} "{$:MailingAddress}"	MailingAddress 1313 Mockingbird Lane, Addis Ababa, Transylvania "1313 Mockingbird Lane, Addis Ababa, Transylvania "

Another way you may nest PTVs is to make (part of) the variable name a variable in itself:

Example:
x:Test/Ptvb Contents of y on page {$:x}: {{$:x}$:y}	x:Test/Ptvb Contents of y on page Test/Ptvb:

Usage with pagelists

Page lists can also access the page text variables:

Example:
(:pagelist group=PmWiki order=$:Summary count=6 fmt=#singleline:)	SpecialCharacters, UpgradingFromPmWiki1, WikiSandbox, WikiFarmTerminology, UTF-8, SitePageActions,

And to create pagelist formats (such as those documented at Site.Page List Templates, Page Lists, Page List Templates, Page Variables. Store custom pagelists at Site.Local Templates).

Page lists can also use page text variables to select pages :

Example:
(:pagelist group=PmWiki $:City=Paris count=8 fmt=#singleline order=-name:)

lists pages having '$:City' set to 'Paris'.

Example: multiple selections
(:pagelist group=PmWiki $:Audience="authors (intermediate),administrators (intermediate)" order=-$:Audience,name count=10 fmt=#singleline:)	Categories, GroupHeaders, IncludeOtherPages, Page specific variables, Table directives, Uploads, AuthUser, CustomMarkup, CustomWikiStyles, GroupCustomizations,

lists pages having a '$:Audience' of 'authors (intermediate)' or 'administrators (intermediate)'.

Example: multiple selections with spaces
(:pagelist group=PmWiki $:City="Addis Ababa,Paris" order=-$:Version count=8 fmt=#singleline:)	PageTextVariables,

'quotes' must surround all the selections.

Example: Pages with City variable set
City: Addis Ababa (:pagelist group=PmWiki $:City=- count=10 fmt=#singleline:)	City: Addis Ababa PageTextVariables,

City variable is set.

When using page text variables for selection or ordering, don't put the curly braces around the variable name. The curly forms do a replacement before the pagelist command is evaluated.

Testing if set or not set

=-	PTV is set (is not empty), eg `(:pagelist $:MyPageTextVariable=- :)`
=-?*	PTV is not set (is empty), ie is not set to one char followed by 0 or more chars, eg `(:pagelist $:MyPageTextVariable=-?* :)`
=*	display all pages, the page text variable is irrelevant
=-*	display no pages, the page text variable is irrelevant

Example: Pages without a summary
(:pagelist group=PmWiki $:Summary=-?* count=6 fmt=#singleline:)	Introduction, PatrickMichaud, PmWiki, SitePageActions, SpecialCharacters, UpgradingFromPmWiki1,

Use page text variable in a template

Display pages by Audience page text variable.

Example:
>>comment<< [[#byaudience]] (:if ! equal '{=$:Audience}' '{<$:Audience}':) -<'''{=$:Audience}''': (:ifend:) [[{=$Name}]] [[#byaudienceend]] >><< (:pagelist group=PmWiki count=10 fmt=#byaudience order=-$:Audience:)	{=$:Audience}: {=$Name}? visitors (intermediate) : WebFeeds AccessKeys authors, admins (intermediate) : PageLists authors, admins (advanced) : ConditionalMarkup authors (intermediate) : PageVariables IncludeOtherPages Categories TableDirectives GroupHeaders Uploads

Use page text variables in conditional markup

Page text variables will be assigned/evaluated before any conditional markup is evaluated. That means you can use page text variables with conditional markup, but not conditional markup within page text variables. For instance a PTV will have a value even if it is set within a (:if false:)....(:if:) condition.

Usage - other

Data relevant to a page (the "Base" page) may now also be found in other groups. If the Base page is Main/HomePage, the data page could be Data-Main/HomePage. A new variable called $BaseName, which automatically calculates the Base page name from the Data page name, and can be defined by including the following in config.php:

// The pattern for figuring out the basename of a page
$BaseNamePatterns['/^Data-/'] = '';

Your pattern may vary.

Usage - from within code (developers only)

The standard PageVar($pagename,$varname) function can return page text variables, but remember to include the dollar and colon like this:

$var=PageVar($pagename,'$:City')

Actually, for text variables, PageVar just calls PageTextVar($pagename,$varname), so your code can be sped up slightly by calling it directly, but it takes just the raw variable name without any leading characters, like this:

$var=PageTextVar($pagename,'City')

It works by caching all page text-variables it finds in a page (in $PCache) and returns the one requested.