caption: duplicateslugs
created: 20200509141702846
modified: 20200509141702846
op-input: a [[selection of titles|Title Selection]]
op-output: the input titles transformed so that they only contain lower case letters, numbers, periods, dashes and underscores
op-purpose: returns each item in the list in a human-readable form for use in URLs or filenames
tags: [[Filter Operators]]
title: duplicateslugs Operator
type: text/vnd.tiddlywiki

<<.from-version "5.1.23">> The <<.olink slugify>> can be used to transform arbitrary tiddler titles into human readable strings suitable for use in URLs or filenames. However, itis possible for multiple different titles to slugify to the same string. The <<.olink duplicateslugs>> operator can be used to display a warning. For example:

<$macrocall $name='wikitext-example-without-html'
src='<$list filter="[!is[system]duplicateslugs[]limit[1]]" emptyMessage="There are no duplicate slugs">
The following tiddlers have duplicate slugs:

<ul>
<$list filter="[!is[system]duplicateslugs[]]">
<li><$link><$text text=<<currentTiddler>>/></$link></li>
</$list>
</ul>
</$list>'/>
