Difference: TWikiVariables (86 vs. 87)

Revision 872011-03-27 - TWikiContributor

Line: 1 to 1
 
META TOPICPARENT name="WebHome"

TWiki Variables

Line: 75 to 78
  You can also set preferences variables on a topic by clicking the link Edit topic preference settings under More topic actions. Use the same * Set VARIABLENAME = value syntax. Preferences set in this manner are not visible in the topic text, but take effect nevertheless.
Added:
>
>

Parameterized Variables (Macros)

It is possible to pass parameters to TWiki variables. This is called a macro in a programming language.

To define a parameterized variable, set a variable that contains other variables, such as:

   * Set EXAMPLE = Example variable using %DEFAULT%, %PARAM1% and %PARAM2%
   * Set DEMO = Demo using %DEFAULT{ default="(undefined)" }%,
                %PARAM1{ default="(undefined)" }% and %PARAM2{ default="(undefined)" }%

A special %DEFAULT% variable denotes the default (nameless) parameter of the calling variable. Variables optionally may list a default="..." parameter that gets used in case the calling variable does not specify that parameter.

To use a parameterized variable (or call a macro), add parameters within the curly brackets, such as:

   * %EXAMPLE{ "foo" PARAM1="bar" PARAM2="baz" }%
   * %DEMO{ "demo" PARAM2="parameter 2" }% -- note that PARAM1 is missing
which resolves to:
  • Example variable using foo, bar and baz
  • Demo using demo, (undefined) and parameter 2 -- note that PARAM1 is missing

Parameters in the variable definition are expanded using the following sequence:

  1. Parameter from variable call. In above example, %PARAM1% gets expanded to bar.
  2. Session variable and preferences settings

Example

Define variables:

   * Set DRINK = red wine
   * Set FAVORITE = My %DEFAULT{default="favorite"}% dish is %DISH{default="steak"}%,
                    my %DEFAULT{default="favorite"}% drink is %DRINK%.
TIP The default can be defined with a default parameter (%DISH{default="steak"}%), or as a preferences setting (Set DRINK = ...).

Use Variables:

%FAVORITE{ DISH="Sushi" DRINK="Sake" }%
Returns:
My favorite dish is Sushi, my favorite drink is Sake.

%FAVORITE{}%
Returns:
My favorite dish is steak, my favorite drink is red wine.

%FAVORITE{ "preferred" }%
Returns:
My preferred dish is steak, my preferred drink is red wine.

<--
Defined in INCLUDE: 
  • Set EXAMPLE = Example variable using %DEFAULT%, %PARAM1% and %PARAM2%
  • Set DEMO = Demo using %DEFAULT{ default="(undefined)" }%, %PARAM1{ default="(undefined)" }% and %PARAM2{ default="(undefined)" }%
  • Set DRINK = red wine
  • Set FAVORITE = My %DEFAULT{default="favorite"}% dish is %DISH{default="steak"}%, my %DEFAULT{default="favorite"}% drink is red wine.
-->
 

Access Control Variables

These are special types of preferences variables to control access to content. TWikiAccessControl explains these security settings in detail.

Line: 149 to 165
 
Changed:
<
<
Related Topics: UserDocumentationCategory, TWikiVariablesSearch, TWikiVariablesQuickStart
>
>
Related Topics: UserDocumentationCategory, TWikiVariablesSearch, TWikiVariablesQuickStart, ParameterizedVariables
 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright © 1999-2024 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback
Note: Please contribute updates to this topic on TWiki.org at TWiki:TWiki.TWikiVariables.