diff --git a/rkward/syntax/r.xml b/rkward/syntax/r.xml
index 2760b30c..8e6d0b18 100644
--- a/rkward/syntax/r.xml
+++ b/rkward/syntax/r.xml
@@ -1,152 +1,153 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE language SYSTEM "language.dtd">
 <!-- Kate 2.5 (KDE 3.5) highlighting module for R
 	based on an earlier version by E.L. Willighagen. Code folding code by Ben Goodrich
 	version 2.0: (c) 2006 Thomas Friedrichsmeier, Arne Henningsen, and the RKWard Team
 	license: GPL v2
 	Kate   : http://kate.kde.org/
 	R      : http://www.r-project.org/
 	RKWard : http://rkward.kde.org/
 	-->
 <language version="8" kateversion="5.0" name="R Script" section="Scientific" extensions="*.R;*.r;*.S;*.s;*.q" mimetype="" license="GPLv2">
 <highlighting>
 
 	<list name="controls">
 		<item>for</item>
 		<item>in</item>
 		<item>next</item>
 		<item>break</item>
 		<item>while</item>
 		<item>repeat</item>
 		<item>if</item>
 		<item>else</item>
 		<item>switch</item>
 		<item>function</item>
 	</list>
 	<list name="words">
 		<item>TRUE</item>
 		<item>FALSE</item>
 		<item>NULL</item>
 		<item>NA</item>
 		<item>NA_integer_</item>
 		<item>NA_real_</item>
 		<item>NA_complex_</item>
 		<item>NA_character_</item>
 		<item>Inf</item>
 		<item>NaN</item>
 	</list>
 
 	<contexts>
 		<!-- This context is really only good for detecting unexpected closing braces '}'. Since opening braces go to ctx0 (and nesting in there), this context is only active on the base level -->
 		<context attribute="Normal Text" lineEndContext="#stay" name="level0">
 			<IncludeRules context="CommonRules"/>
 
 			<DetectChar attribute="Error" context="#stay" char="}" />
 			<DetectChar attribute="Error" context="#stay" char=")"/>
 		</context>
 
 		<context attribute="Normal Text" lineEndContext="#stay" name="ctx0">
 			<IncludeRules context="CommonRules"/>
 
 			<DetectChar attribute="Symbol" context="#pop" char="}" endRegion="Brace1" />
 			<DetectChar attribute="Error" context="#stay" char=")"/>
 		</context>
 
 		<context attribute="Normal Text" lineEndContext="#stay" name="parenthesis">
 			<LineContinue attribute="Operator" context="#stay"/>
 			<DetectChar attribute="Symbol" context="#pop" char=")"/>
 
 			<RegExpr attribute="Identifier" context="#stay" String="[a-zA-Z_\.][0-9a-zA-Z_\.]*[\s]*=(?=([^=]|$))"/>
 
 			<IncludeRules context="CommonRules"/>
 			<DetectChar attribute="Error" context="#stay" char="}" />
 		</context>
 
 		<context attribute="String" lineEndContext="#stay" name="string">
 			<DetectChar attribute="String" context="#pop" char="&quot;"/>
 			<HlCStringChar attribute="String Char" context="#stay"/>
 		</context>
 
 		<context attribute="String" lineEndContext="#stay" name="string2">
 			<DetectChar attribute="String" context="#pop" char="'"/>
 			<HlCStringChar attribute="String Char" context="#stay"/>
 		</context>
 
 		<context attribute="Identifier" lineEndContext="#stay" name="backquotedsymbol">
 			<DetectChar attribute="String" context="#pop" char="`"/>
 			<HlCStringChar attribute="String Char" context="#stay"/>
 		</context>
 
 		<context attribute="Normal Text" lineEndContext="#stay" name="operator_rhs" fallthrough="true" fallthroughContext="#pop">
 			<!-- While there is nothing of interest, stay in the context -->
 			<StringDetect attribute="Headline" context="Headline" String="##"/>
 			<DetectChar attribute="Comment" context="Comment" char="#"/>
 			<DetectChar attribute="String" context="#stay" char=" "/>
 			<!-- Operators other than +, -, and ! directly after another operator are an error. -->
 			<RegExpr attribute="Error" context="#stay" String="(\*|/|&lt;|&gt;|\!=|=|\||&amp;|:|\^|@|\$|~)"/>
 		</context>
 
 		<context attribute="Headline" lineEndContext="#pop" name="Headline">
 			<IncludeRules context="##Alerts" />
 		</context>
 		<context attribute="Comment" lineEndContext="#pop" name="Comment">
 			<IncludeRules context="##Alerts" />
 		</context>
 
 		<!-- This context is not really used, but contains the common rules -->
 		<context name="CommonRules" lineEndContext="#stay" attribute="Normal Text" >
 			<DetectChar attribute="String" context="string" char="&quot;"/>
 			<DetectChar attribute="String" context="string2" char="'"/>
 			<DetectChar attribute="String" context="backquotedsymbol" char="`"/>
 			<keyword attribute="Control Structure" context="#stay" String="controls"/>
 			<keyword attribute="Reserved Words" context="#stay" String="words"/>
 			<Float attribute="Float" context="#stay"/>
 			<Int attribute="Int" context="#stay"/>
 			<RegExpr attribute="Keyword" context="#stay" String="[a-zA-Z_]+[a-zA-Z_\.0-9]*(?=[\s]*[(])"/>
 			<RegExpr attribute="Keyword" context="#stay" String="\.[a-zA-Z_\.]+[a-zA-Z_\.0-9]*(?=[\s]*[(])"/>
 			<RegExpr attribute="Symbol" context="parenthesis" String="\("/>
 			<StringDetect attribute="Headline" context="Headline" String="##"/>
 			<DetectChar attribute="Comment" context="Comment" char="#"/>
 
 			<!-- For (assignment) operators, enter a new context operator_rhs to check what follows (generally, that should not be another op) -->
 			<RegExpr attribute="Assign" context="operator_rhs" String="[&lt;]{1,2}\-"/>
 			<RegExpr attribute="Assign" context="operator_rhs" String="\-[&gt;]{1,2}"/>
 			<RegExpr attribute="Assign" context="operator_rhs" String="=(?!=)"/>
+			<RegExpr attribute="Assign" context="operator_rhs" String=":="/>
 			<RegExpr attribute="Operator" context="operator_rhs" String="(\+|\-|\*{1,2}|/|&lt;=?|&gt;=?|={1,2}|\!=?|\|{1,2}|&amp;{1,2}|:{1,3}|\^|@|\$|~)"/>
 			<RegExpr attribute="Operator" context="operator_rhs" String="%[^%]*%"/>
 
 			<DetectChar attribute="Symbol" context="ctx0" char="{" beginRegion="Brace1" />
 
 			<!-- This is needed only to assist variable based indentation -->
 			<DetectChar attribute="Symbol" context="#stay" char="[" />
 			<DetectChar attribute="Symbol" context="#stay" char="]" />
 		</context>
 	</contexts>
 
 	<itemDatas>
 		<!-- KDE default colors: http://accessibility.kde.org/oxygen.php?color=white -->
 		<itemData name="Normal Text" defStyleNum="dsNormal"/>
 		<itemData name="Symbol" defStyleNum="dsNormal"/>
 		<itemData name="Keyword" defStyleNum="dsKeyword"/>
 		<itemData name="Identifier" defStyleNum="dsDataType"/>
 		<itemData name="String" defStyleNum="dsString"/>
 		<itemData name="Headline" defStyleNum="dsComment" color="#b00000" selColor="#b00000" bold="1" italic="0"/> <!-- KDE default color: text 5 -->
 		<itemData name="Comment" defStyleNum="dsComment"/>
 		<itemData name="Assign" defStyleNum="dsNormal" color="#336366" selColor="#ccc099" bold="1" italic="0"/> <!-- KDE default color: text 7 -->
 		<itemData name="Control Structure" defStyleNum="dsControlFlow"/>
 		<itemData name="Reserved Words" defStyleNum="dsOthers"/>
 		<itemData name="Error" defStyleNum="dsError"/>
 		<itemData name="Operator" defStyleNum="dsOperator"/>
 		<itemData name="String Char"  defStyleNum="dsChar"/>
 		<itemData name="Float" defStyleNum="dsFloat"/>
 		<itemData name="Int" defStyleNum="dsDecVal"/>
 	</itemDatas>
 </highlighting>
 
 <general>
 	<comments>
 		<comment name="singleLine" start="#" end=""/>
 	</comments>
 	<keywords casesensitive="true" weakDeliminator="." additionalDeliminator="$"/>
 </general>
 </language>