created: 20220917113154900
modified: 20230518143557045
tags: Pragmas
title: Pragma: \parameters
type: text/vnd.tiddlywiki

<<.from-version "5.3.0">> The ''\parameters'' [[pragma|Pragmas]] is used within [[procedure|Procedure Definitions]] and [[widget|Custom Widgets]] definitions to declare the parameters that are expected, and their default values. It is a shortcut syntax for the ParametersWidget.

```
\parameters (<name>[:<default-value>],<name>[:<default-value>]...)
```

For example:

```
\parameters (firstname:"Joe",lastname:"Blogs")
```

To illustrate the use of ''\parameters'' pragma, see [[Core Icons]] which are parameterised. The first parameter `size` specified the size at which the icon should be rendered. For example see the text of [[$:/core/images/print-button]] tiddler. The first line defines the size parameter as `\parameters (size:"22pt")`

<<wikitext-example-without-html """{{$:/core/images/print-button|16px}}
<$transclude $tiddler="$:/core/images/print-button" size="32px"/>
""">>

In the above example, the first line shows a simple transclusion of [[$:/core/images/print-button]] icon with `size` parameter passed by position and is set to 16px. The second line is a transclusion of image with `size` parameter passed by name and is set to 32px.