DekiScript Primer

Motivation for DekiScript

• Use Case– Embed dynamic content– Create dynamic layouts– Anybody can use it safely (i.e. not JavaScript)

• Design principles– Not case-sensitive– Simple data types– Native support for XML– Concurrent (e.g. write-once, read-many)

Data Types

Type Value

Nil nil, null, _

Bool true, false

Number (num) 123, -1.23e4

String (str) “hi”, ‘bye’

List [ 1, 2, 3 ]

Map { a: 1, b: 2, c: 3 }

Uri n/a

Xml n/a

Basic Operations

DekiScript Output

{{ nil }}

{{ “1” + “23” }} 24

{{ 1 .. 23 }} 123

{{ [ 1 ] .. [ 2, 3 ] }} [ 1, 2, 3]

{{ { x: 1 } .. { y : 2 } }} { x: 1, y: 2 }

{{ “123” != nil ? “1” : 0 }} 1

{{ nil ?? 123 }} 123

{{ false ?? 123 }} False

{{ #[ 1, 2, 3 ] }} 3

Control Flow Statements

DekiScript

var x = 123;

let x += 1;

if(x) { … } else { … }

foreach(var x in y) { … }

{{ var x = 0; foreach(var y in [ 1, 2, 3, 4 ]) {

if(y % 2 == 0) {let x += y;

}}x;

}}

User object

Properties

user.name User name

user.homepage Homepage object

user.anonymous True if user is not logged in

user.gravatar Gravatar image

user.uri Uri for user homepage

user.api Uri for user web-service

Page object

Properties

page.name Page name

page.title Page title

page.uri Uri for page

page.api Uri for page web-service

page.date Date when page was edited

page.author Last author on page

page.subpages Sub-pages of current page

page.files Files attached to page

page.tags Tags associated with page

Site object

Properties

site.name Name of site

site.hostname Internet hostname

site.api Uri for site web-service

site.uri Uri for site homepage

site.homepage Homepage object

site.feed Uri for site RSS feed

site.pagecount Number of pages on site

site.usercount Number of registered users

Sample: Gravatars

Gravatar for most recent page author

<div style=“float: right;”><center>

{{ page.author.gravatar }}<br/>{{ web.link(user.uri, user.name) }}

</center></div>

Control Flow Attributes

DekiScript Attributes

<div block=“var f = page.files”>…</div>

<ul if=“#f”>…</ul>

<li foreach=“var x in page.files” where=“string.endswith(x.name, ‘.doc’)”>

…</li>

<span init=“var f = page.files” if=“#f”>…</span>

Sample: Gravatars, The Sequel

Gravatars for sub-page authors

<table init=“var s = page.subpages” if=“#s” class=“table”><tr>

<th>Title</th><th>Author</th><th>Gravatar</th>

</tr><tr foreach=“var p in s” class=“{{__count % 2 ? ‘bg2’ : ‘bg1’}}” >

<td>{{ web.link(p.uri, p.title) }}</td><td>{{ web.link(p.author.uri, p.author.name) }}</td><td>{{ p.author.gravatar }}</td>

</tr></table>

Finding Functions

Advanced Constructs

Construct

{{save: … }} Substitute on save

{{edit: …}} Substitute on edit

<p class=“noinclude”> Hide when included

<p class=“includeonly”> Show only when included

<pre|span class=“script”> Contents is script<pre class=“script”function=“syntax.xml($, true)”>

Content transforms

$ Template parameters

__request.args Query request parameters

Sample: Custom Search Form

Embed a form for constrained search

Use this page to only search pages tagged with "extensions":{{ dhtml.inputbox{value: __request.args.q, button: "Search", field: "q", publish: page.uri} }}

{{ if(__request.args.q) { wiki.search(__request.args.q, _, _, "tag:extensions")

} }}

Sample: Notebook

Simple notebook application

<p>{{ wiki.create{ label: "Add a note", template: "NotebookPage", title: date.format(date.now, "yyyy MMMM, d") ..

' (' .. user.name .. ')' } }}</p><ul> <li foreach="var p in page.subpages">

{{web.link(p.uri, p.title)}} <span style="color: rgb(128, 128, 128); font-size: small;”>

({{#p.comments}} comments)</span><br />{{ var h = wiki.page(p.path); h["//*[@class='summary']"] }}

</li></ul>

Questions?

• Slides and samples available at– http://wiki.developer.mindtouch.com/DekiCon

• Discussion forums at– http://forums.developer.mindtouch.com

• Latest news at– http://www.mindtouch.com/blog