mirror of
https://github.com/Jermolene/TiddlyWiki5
synced 2024-11-15 22:34:51 +00:00
92 lines
3.6 KiB
Plaintext
92 lines
3.6 KiB
Plaintext
caption: set
|
|
created: 20131115182700000
|
|
modified: 20180315165405442
|
|
tags: Widgets
|
|
title: SetWidget
|
|
type: text/vnd.tiddlywiki
|
|
|
|
! Introduction
|
|
|
|
The set variable widget assigns a value to a specified [[variable|Variables]]. The new value of the variable is available to the content within the set variable widget.
|
|
|
|
! Content and Attributes
|
|
|
|
The content of the `<$set>` widget is the scope for the value assigned to the variable.
|
|
|
|
|!Attribute |!Description |
|
|
|name |The name of the variable to assign (defaults to "currentTiddler") |
|
|
|value |The value to assign to the variable if the filter is missing or not empty |
|
|
|tiddler |<<.from-version "5.1.15">> Optional title of the tiddler from which to read the value |
|
|
|subtiddler |<<.from-version "5.1.16">> Optionally specifies the title of a subtiddler within a plugin tiddler identified by the ''tiddler'' attribute |
|
|
|field |<<.from-version "5.1.15">> Optional field of the tiddler from which to read the value (only used if ''tiddler'' is used) |
|
|
|index |<<.from-version "5.1.15">> Optional index of the tiddler from which to read the value (only used if ''tiddler'' is used) |
|
|
|filter |An optional filter to be evaluated and assigned to the variable (see below) |
|
|
|select |<<.from-version "5.1.14">> An optional zero-based index of the item to return from the filter output (see below) |
|
|
|emptyValue |The value to assign to the variable if the specified value is missing or empty (see below) |
|
|
|
|
!! Simple Variable Assignment
|
|
|
|
The simplest way of using set variable widget assigns a string to a variable. The following example assigns a literal string
|
|
|
|
```
|
|
<$set name="myVariable" value="Some text">
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|
|
|
|
Both the name and value attributes can be transcluded. For example:
|
|
|
|
```
|
|
<$set name=<<anotherVariable>> value={{template!!text}}>
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|
|
|
|
!! Conditional Variable Assignment
|
|
|
|
This form of the set variable widget chooses one of two specified values according to whether a filter evaluates to an empty list. Here's an example that sets a variable according to whether the current tiddler is called "myMagicTitle":
|
|
|
|
```
|
|
<$set name="myVariable" filter="[all[current]field:title[myMagicTitle]]" value="It's magic" emptyValue="It's not magic">
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|
|
|
|
!! Filtered List Variable Assignment
|
|
|
|
This form of the set variable widget evaluates the filter and assigns the result to the variable as a space-separated list (using double square brackets for titles containing spaces).
|
|
|
|
```
|
|
<$set name="myVariable" filter="[tag[HelloThere]]">
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|
|
|
|
!! Filtered Item Variable Assignment
|
|
|
|
<<.from-version "5.1.14">> This form of the set variable widget evaluates the filter and assigns the specified result to the variable as a single item (ie, not using double square brackets for titles containing spaces).
|
|
|
|
```
|
|
<$set name="myVariable" filter="[tag[HelloThere]]" select="0">
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|
|
|
|
!! Transcluded Variable Assignment
|
|
|
|
<<.from-version "5.1.15">> This form of the set variable widget obtains the value to assign to the variable from a value in a tiddler field or index. For example:
|
|
|
|
```
|
|
<$set name="myVariable" tiddler="HelloThere" field="text">
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|
|
|
|
The example above could also be written as `<$set name="myVariable" value={{HelloThere!!text}}>`. The advantage of using the ''tiddler'' attribute is that the tiddler title and field or index can themselves be computed. For example:
|
|
|
|
```
|
|
<$set name="myVariable" tiddler=<<myTiddler>> field={{$:/currentField}}>
|
|
<$text text=<<myVariable>>/>
|
|
</$set>
|
|
```
|