fix: improve local style management for activity diagrams

https://github.com/plantuml/plantuml/issues/1629

gradle.properties

@@ -1,4 +1,4 @@
 # Warning, "version" should be the same in gradle.properties and Version.java
 # Any idea anyone how to magically synchronize those :-) ?
-version = 1.2023.14beta1
+version = 1.2023.14beta2
 org.gradle.workers.max = 3

src/net/sourceforge/plantuml/activitydiagram3/InstructionRepeat.java

@@ -59,6 +59,7 @@ import net.sourceforge.plantuml.sequencediagram.NotePosition;
 import net.sourceforge.plantuml.sequencediagram.NoteType;
 import net.sourceforge.plantuml.stereo.Stereotype;
 import net.sourceforge.plantuml.style.ISkinParam;
+import net.sourceforge.plantuml.style.StyleBuilder;
 
 public class InstructionRepeat extends AbstractInstruction implements Instruction {
 
@@ -87,6 +88,7 @@ public class InstructionRepeat extends AbstractInstruction implements Instructio
 	private LinkRendering endRepeatLinkRendering = LinkRendering.none();
 
 	private final Colors colors;
+	private final StyleBuilder currentStyleBuilder;
 
 	public boolean containsBreak() {
 		return repeatList.containsBreak();
@@ -94,6 +96,7 @@ public class InstructionRepeat extends AbstractInstruction implements Instructio
 
 	public InstructionRepeat(Swimlanes swimlanes, Instruction parent, LinkRendering nextLinkRenderer, HColor color,
 			Display startLabel, BoxStyle boxStyleIn, Colors colors) {
+		this.currentStyleBuilder = swimlanes.getCurrentStyleBuilder();
 		this.swimlanes = swimlanes;
 		this.swimlane = swimlanes.getCurrentSwimlane();
 		this.repeatList = new InstructionList(this.swimlane);
@@ -158,7 +161,7 @@ public class InstructionRepeat extends AbstractInstruction implements Instructio
 		if (this.testCalled == false && incoming1.isNone())
 			incoming1 = swimlanes.nextLinkRenderer();
 		final Ftile result = factory.repeat(boxStyleIn, swimlane, swimlaneOut, startLabel, decorateOut, test, yes, out,
-				colors, back, isLastOfTheParent(), incoming1, incoming2);
+				colors, back, isLastOfTheParent(), incoming1, incoming2, currentStyleBuilder);
 		if (killed)
 			return new FtileKilled(result);
 

src/net/sourceforge/plantuml/activitydiagram3/InstructionWhile.java

@@ -56,6 +56,7 @@ import net.sourceforge.plantuml.klimt.geom.VerticalAlignment;
 import net.sourceforge.plantuml.sequencediagram.NotePosition;
 import net.sourceforge.plantuml.sequencediagram.NoteType;
 import net.sourceforge.plantuml.style.ISkinParam;
+import net.sourceforge.plantuml.style.StyleBuilder;
 
 public class InstructionWhile extends WithNote implements Instruction, InstructionCollection {
 
@@ -82,6 +83,7 @@ public class InstructionWhile extends WithNote implements Instruction, Instructi
 	private LinkRendering incoming1 = LinkRendering.none();
 	private LinkRendering incoming2 = LinkRendering.none();
 	private boolean backwardCalled;
+	private final StyleBuilder currentStyleBuilder;
 
 	public void overwriteYes(Display yes) {
 		this.yes = yes;
@@ -94,6 +96,7 @@ public class InstructionWhile extends WithNote implements Instruction, Instructi
 		this.nextLinkRenderer = Objects.requireNonNull(nextLinkRenderer);
 		this.yes = Objects.requireNonNull(yes);
 		this.swimlane = swimlane;
+		this.currentStyleBuilder = skinParam.getCurrentStyleBuilder();
 		this.color = color;
 		this.skinParam = skinParam;
 	}
@@ -118,7 +121,7 @@ public class InstructionWhile extends WithNote implements Instruction, Instructi
 		final Ftile back = Display.isNull(backward) ? null
 				: factory.activity(backward, swimlane, boxStyle, Colors.empty(), null);
 		Ftile tmp = repeatList.createFtile(factory);
-		tmp = factory.createWhile(outColor, swimlane, tmp, test, yes, color, specialOut, back, incoming1, incoming2);
+		tmp = factory.createWhile(outColor, swimlane, tmp, test, yes, color, specialOut, back, incoming1, incoming2, currentStyleBuilder);
 		if (getPositionedNotes().size() > 0)
 			tmp = FtileWithNoteOpale.create(tmp, getPositionedNotes(), false, VerticalAlignment.CENTER);
 

src/net/sourceforge/plantuml/activitydiagram3/ftile/FtileFactory.java

@@ -84,10 +84,11 @@ public interface FtileFactory {
 
 	public Ftile repeat(BoxStyle boxStyleIn, Swimlane swimlane, Swimlane swimlaneOut, Display startLabel, Ftile repeat,
 			Display test, Display yes, Display out, Colors colors, Ftile backward, boolean noOut,
-			LinkRendering incoming1, LinkRendering incoming2);
+			LinkRendering incoming1, LinkRendering incoming2, StyleBuilder currentStyleBuilder);
 
 	public Ftile createWhile(LinkRendering outColor, Swimlane swimlane, Ftile whileBlock, Display test, Display yes,
-			HColor color, Instruction specialOut, Ftile backward, LinkRendering incoming1, LinkRendering incoming2);
+			HColor color, Instruction specialOut, Ftile backward, LinkRendering incoming1, LinkRendering incoming2,
+			StyleBuilder currentStyleBuilder);
 
 	public Ftile createIf(Swimlane swimlane, List<Branch> thens, Branch elseBranch, LinkRendering outColor,
 			LinkRendering topInlinkRendering, Url url, Collection<PositionedNote> notes, Stereotype stereotype,

src/net/sourceforge/plantuml/activitydiagram3/ftile/FtileFactoryDelegator.java

@@ -175,16 +175,17 @@ public class FtileFactoryDelegator implements FtileFactory {
 	@Override
 	public Ftile repeat(BoxStyle boxStyleIn, Swimlane swimlane, Swimlane swimlaneOut, Display startLabel, Ftile repeat,
 			Display test, Display yes, Display out, Colors colors, Ftile backward, boolean noOut,
-			LinkRendering incoming1, LinkRendering incoming2) {
+			LinkRendering incoming1, LinkRendering incoming2, StyleBuilder currentStyleBuilder) {
 		return factory.repeat(boxStyleIn, swimlane, swimlaneOut, startLabel, repeat, test, yes, out, colors, backward,
-				noOut, incoming1, incoming2);
+				noOut, incoming1, incoming2, currentStyleBuilder);
 	}
 
 	@Override
 	public Ftile createWhile(LinkRendering outColor, Swimlane swimlane, Ftile whileBlock, Display test, Display yes,
-			HColor color, Instruction specialOut, Ftile back, LinkRendering incoming1, LinkRendering incoming2) {
+			HColor color, Instruction specialOut, Ftile back, LinkRendering incoming1, LinkRendering incoming2,
+			StyleBuilder styleBuilder) {
 		return factory.createWhile(outColor, swimlane, whileBlock, test, yes, color, specialOut, back, incoming1,
-				incoming2);
+				incoming2, styleBuilder);
 	}
 
 	@Override

src/net/sourceforge/plantuml/activitydiagram3/ftile/Swimlanes.java

@@ -82,6 +82,7 @@ import net.sourceforge.plantuml.style.ISkinParam;
 import net.sourceforge.plantuml.style.PName;
 import net.sourceforge.plantuml.style.SName;
 import net.sourceforge.plantuml.style.Style;
+import net.sourceforge.plantuml.style.StyleBuilder;
 import net.sourceforge.plantuml.style.StyleSignatureBasic;
 import net.sourceforge.plantuml.style.Styleable;
 import net.sourceforge.plantuml.svek.UGraphicForSnake;
@@ -127,9 +128,9 @@ public class Swimlanes extends AbstractTextBlock implements TextBlock, Styleable
 	}
 
 	protected Style getStyle() {
-		if (style == null) {
+		if (style == null)
 			this.style = getStyleSignature().getMergedStyle(skinParam.getCurrentStyleBuilder());
-		}
+
 		return style;
 	}
 
@@ -455,4 +456,8 @@ public class Swimlanes extends AbstractTextBlock implements TextBlock, Styleable
 		return cachedMinMax;
 	}
 
+	public StyleBuilder getCurrentStyleBuilder() {
+		return skinParam.getCurrentStyleBuilder();
+	}
+
 }

src/net/sourceforge/plantuml/activitydiagram3/ftile/vcompact/FtileFactoryDelegatorRepeat.java

@@ -62,6 +62,7 @@ import net.sourceforge.plantuml.klimt.font.FontConfiguration;
 import net.sourceforge.plantuml.klimt.geom.XDimension2D;
 import net.sourceforge.plantuml.style.PName;
 import net.sourceforge.plantuml.style.Style;
+import net.sourceforge.plantuml.style.StyleBuilder;
 import net.sourceforge.plantuml.svek.ConditionStyle;
 
 public class FtileFactoryDelegatorRepeat extends FtileFactoryDelegator {
@@ -73,13 +74,12 @@ public class FtileFactoryDelegatorRepeat extends FtileFactoryDelegator {
 	@Override
 	public Ftile repeat(BoxStyle boxStyleIn, Swimlane swimlane, Swimlane swimlaneOut, Display startLabel,
 			final Ftile repeat, Display test, Display yes, Display out, Colors colors, Ftile backward, boolean noOut,
-			LinkRendering incoming1, LinkRendering incoming2) {
+			LinkRendering incoming1, LinkRendering incoming2, StyleBuilder currentStyleBuilder) {
 
 		final ConditionStyle conditionStyle = skinParam().getConditionStyle();
 
-		final Style styleArrow = getDefaultStyleDefinitionArrow().getMergedStyle(skinParam().getCurrentStyleBuilder());
+		final Style styleArrow = getDefaultStyleDefinitionArrow().getMergedStyle(currentStyleBuilder);
-		final Style styleDiamond = getDefaultStyleDefinitionDiamond()
+		final Style styleDiamond = getDefaultStyleDefinitionDiamond().getMergedStyle(currentStyleBuilder);
-				.getMergedStyle(skinParam().getCurrentStyleBuilder());
 		final HColor borderColor = styleDiamond.value(PName.LineColor).asColor(skinParam().getIHtmlColorSet());
 		final HColor diamondColor = styleDiamond.value(PName.BackGroundColor).asColor(skinParam().getIHtmlColorSet());
 		final Rainbow arrowColor = Rainbow.build(styleArrow, skinParam().getIHtmlColorSet());

src/net/sourceforge/plantuml/activitydiagram3/ftile/vcompact/FtileFactoryDelegatorWhile.java

@@ -58,6 +58,7 @@ import net.sourceforge.plantuml.klimt.drawing.UGraphic;
 import net.sourceforge.plantuml.klimt.font.FontConfiguration;
 import net.sourceforge.plantuml.style.PName;
 import net.sourceforge.plantuml.style.Style;
+import net.sourceforge.plantuml.style.StyleBuilder;
 import net.sourceforge.plantuml.svek.ConditionStyle;
 
 public class FtileFactoryDelegatorWhile extends FtileFactoryDelegator {
@@ -68,13 +69,13 @@ public class FtileFactoryDelegatorWhile extends FtileFactoryDelegator {
 
 	@Override
 	public Ftile createWhile(LinkRendering outColor, Swimlane swimlane, Ftile whileBlock, Display test, Display yes,
-			HColor color, Instruction specialOut, Ftile backward, LinkRendering incoming1, LinkRendering incoming2) {
+			HColor color, Instruction specialOut, Ftile backward, LinkRendering incoming1, LinkRendering incoming2,
+			StyleBuilder currentStyleBuilder) {
 
 		final ConditionStyle conditionStyle = skinParam().getConditionStyle();
 
-		final Style styleArrow = getDefaultStyleDefinitionArrow().getMergedStyle(skinParam().getCurrentStyleBuilder());
+		final Style styleArrow = getDefaultStyleDefinitionArrow().getMergedStyle(currentStyleBuilder);
-		final Style styleDiamond = getDefaultStyleDefinitionDiamond()
+		final Style styleDiamond = getDefaultStyleDefinitionDiamond().getMergedStyle(currentStyleBuilder);
-				.getMergedStyle(skinParam().getCurrentStyleBuilder());
 		final HColor borderColor = styleDiamond.value(PName.LineColor).asColor(skinParam().getIHtmlColorSet());
 		final HColor backColor = styleDiamond.value(PName.BackGroundColor).asColor(skinParam().getIHtmlColorSet());
 		final Rainbow arrowColor = Rainbow.build(styleArrow, skinParam().getIHtmlColorSet());

src/net/sourceforge/plantuml/activitydiagram3/ftile/vcompact/VCompactFactory.java

@@ -156,14 +156,14 @@ public class VCompactFactory implements FtileFactory {
 	@Override
 	public Ftile repeat(BoxStyle boxStyleIn, Swimlane swimlane, Swimlane swimlaneOut, Display startLabel, Ftile repeat,
 			Display test, Display yes, Display out, Colors colors, Ftile backward, boolean noOut,
-			LinkRendering incoming1, LinkRendering incoming2) {
+			LinkRendering incoming1, LinkRendering incoming2, StyleBuilder currentStyleBuilder) {
 		return repeat;
 	}
 
 	@Override
 	public Ftile createWhile(LinkRendering afterEndwhile, Swimlane swimlane, Ftile whileBlock, Display test,
 			Display yes, HColor color, Instruction specialOut, Ftile back, LinkRendering incoming1,
-			LinkRendering incoming2) {
+			LinkRendering incoming2, StyleBuilder styleBuilder) {
 		return whileBlock;
 	}
 

src/net/sourceforge/plantuml/ebnf/ETileLookAheadOrBehind.java

@@ -0,0 +1,110 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2020, Arnaud Roques
+ *
+ * Project Info:  https://plantuml.com
+ * 
+ * If you like this project or if you find it useful, you can support us at:
+ * 
+ * https://plantuml.com/patreon (only 1$ per month!)
+ * https://plantuml.com/paypal
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ *
+ */
+package net.sourceforge.plantuml.ebnf;
+
+import net.sourceforge.plantuml.klimt.UStroke;
+import net.sourceforge.plantuml.klimt.UTranslate;
+import net.sourceforge.plantuml.klimt.color.HColor;
+import net.sourceforge.plantuml.klimt.color.HColorSet;
+import net.sourceforge.plantuml.klimt.drawing.UGraphic;
+import net.sourceforge.plantuml.klimt.font.FontConfiguration;
+import net.sourceforge.plantuml.klimt.font.StringBounder;
+import net.sourceforge.plantuml.klimt.geom.XDimension2D;
+import net.sourceforge.plantuml.klimt.shape.URectangle;
+import net.sourceforge.plantuml.klimt.shape.UText;
+import net.sourceforge.plantuml.style.PName;
+import net.sourceforge.plantuml.style.Style;
+
+public class ETileLookAheadOrBehind extends ETile {
+
+	private final ETile orig;
+	private final HColorSet colorSet;
+	private final double deltax1 = 4;
+	private final double deltax2 = 8;
+	private final double deltay = 6;
+	private final Style style;
+	private final UText supText;
+
+	private final FontConfiguration fc;
+
+	public ETileLookAheadOrBehind(ETile orig, FontConfiguration fc, Style style, HColorSet colorSet, String type) {
+		this.style = style;
+		this.orig = orig;
+		this.fc = fc;
+		this.colorSet = colorSet;
+		this.supText = UText.build(type, fc);
+
+	}
+
+	@Override
+	public double getH1(StringBounder stringBounder) {
+		return deltay + orig.getH1(stringBounder);
+	}
+
+	@Override
+	public double getH2(StringBounder stringBounder) {
+		return orig.getH2(stringBounder) + deltay;
+	}
+
+	@Override
+	public double getWidth(StringBounder stringBounder) {
+		return orig.getWidth(stringBounder) + deltax1 + deltax2 + supText.calculateDimension(stringBounder).getWidth();
+	}
+
+	@Override
+	public void drawU(UGraphic ug) {
+		final StringBounder stringBounder = ug.getStringBounder();
+		final XDimension2D dim = calculateDimension(stringBounder);
+
+		final HColor lineColor = style.value(PName.LineColor).asColor(colorSet);
+
+		final URectangle rect = URectangle.build(dim).rounded(30);
+
+		ug.apply(lineColor).apply(new UStroke(2, 3, 1)).draw(rect);
+		final double posText = getH1(stringBounder) + supText.getDescent(stringBounder);
+
+		ug.apply(new UTranslate(4, 2 + posText)).draw(supText);
+
+		orig.drawU(ug.apply(new UTranslate(deltax1 + supText.calculateDimension(stringBounder).getWidth(), deltay)));
+
+	}
+
+	@Override
+	public void push(ETile tile) {
+		throw new UnsupportedOperationException();
+	}
+
+}

src/net/sourceforge/plantuml/klimt/shape/UText.java

@@ -38,6 +38,7 @@ package net.sourceforge.plantuml.klimt.shape;
 import net.sourceforge.plantuml.klimt.UShape;
 import net.sourceforge.plantuml.klimt.font.FontConfiguration;
 import net.sourceforge.plantuml.klimt.font.StringBounder;
+import net.sourceforge.plantuml.klimt.geom.XDimension2D;
 
 public class UText implements UShape {
 
@@ -83,4 +84,8 @@ public class UText implements UShape {
 		return orientation;
 	}
 
+	public XDimension2D calculateDimension(StringBounder stringBounder) {
+		return stringBounder.calculateDimension(font.getFont(), text);
+	}
+
 }

src/net/sourceforge/plantuml/regexdiagram/PSystemRegex.java

@@ -52,6 +52,7 @@ import net.sourceforge.plantuml.ebnf.ETile;
 import net.sourceforge.plantuml.ebnf.ETileAlternation;
 import net.sourceforge.plantuml.ebnf.ETileBox;
 import net.sourceforge.plantuml.ebnf.ETileConcatenation;
+import net.sourceforge.plantuml.ebnf.ETileLookAheadOrBehind;
 import net.sourceforge.plantuml.ebnf.ETileNamedGroup;
 import net.sourceforge.plantuml.ebnf.ETileOneOrMore;
 import net.sourceforge.plantuml.ebnf.ETileOptional;
@@ -162,6 +163,10 @@ public class PSystemRegex extends TitledDiagram {
 					push(token, Symbol.TERMINAL_STRING1);
 				else if (token.getType() == ReTokenType.GROUP)
 					push(token, Symbol.SPECIAL_SEQUENCE);
+				else if (token.getType() == ReTokenType.LOOK_AHEAD)
+					lookAheadOrBehind(token.getData());
+				else if (token.getType() == ReTokenType.LOOK_BEHIND)
+					lookAheadOrBehind(token.getData());
 				else if (token.getType() == ReTokenType.NAMED_GROUP)
 					namedGroup(token.getData());
 				else if (token.getType() == ReTokenType.CLASS)
@@ -205,6 +210,11 @@ public class PSystemRegex extends TitledDiagram {
 		stack.addFirst(new ETileBox(element.getData(), type, fontConfiguration, style, colorSet, getSkinParam()));
 	}
 
+	private void lookAheadOrBehind(String name) {
+		final ETile arg1 = stack.removeFirst();
+		stack.addFirst(new ETileLookAheadOrBehind(arg1, fontConfiguration, style, colorSet, name));
+	}
+
 	private void namedGroup(String name) {
 		final ETile arg1 = stack.removeFirst();
 		stack.addFirst(new ETileNamedGroup(arg1, fontConfiguration, colorSet, getSkinParam(), name));

src/net/sourceforge/plantuml/regexdiagram/ReTokenType.java

@@ -44,13 +44,19 @@ public enum ReTokenType {
 	ANCHOR, //
 	GROUP, //
 	NAMED_GROUP, //
+	LOOK_AHEAD, //
+	LOOK_BEHIND, //
 	ALTERNATIVE, //
 	PARENTHESIS_OPEN, //
 	PARENTHESIS_CLOSE, //
 	CONCATENATION_IMPLICIT;
 
+	public boolean isNamedGroupOrLookAheadOrLookBehind() {
+		return this == NAMED_GROUP || this == LOOK_AHEAD || this == LOOK_BEHIND;
+	}
+
 	static public boolean needImplicitConcatenation(ReTokenType token1, ReTokenType token2) {
-		if (token1 == NAMED_GROUP)
+		if (token1.isNamedGroupOrLookAheadOrLookBehind())
 			return false;
 		if (token1 == ALTERNATIVE)
 			return false;

src/net/sourceforge/plantuml/regexdiagram/RegexExpression.java

@@ -60,11 +60,22 @@ public class RegexExpression {
 			} else if (current == '|') {
 				result.add(new ReToken(ReTokenType.ALTERNATIVE, "|"));
 				it.jump();
+			} else if (isStartPosixGroup(it)) {
+				final String s = readGroupPosix(it);
+				result.add(new ReToken(ReTokenType.CLASS, s));
 			} else if (current == '[') {
 				final String s = readGroup(it);
 				result.add(new ReToken(ReTokenType.GROUP, s));
 			} else if (isStartComment(it)) {
 				skipComment(it);
+			} else if (isStartLookAhead(it)) {
+				final ReToken token = readLookAhead(it);
+				result.add(token);
+				result.add(new ReToken(ReTokenType.PARENTHESIS_OPEN, "("));
+			} else if (isStartLookBehind(it)) {
+				final ReToken token = readLookBehind(it);
+				result.add(token);
+				result.add(new ReToken(ReTokenType.PARENTHESIS_OPEN, "("));
 			} else if (isStartNamedCapturingGroup(it)) {
 				final ReToken token = readNamedGroup(it);
 				result.add(token);
@@ -102,6 +113,20 @@ public class RegexExpression {
 
 	}
 
+	private static boolean isStartLookAhead(CharInspector it) {
+		final char current0 = it.peek(0);
+		if (current0 == '(' && it.peek(1) == '?' && (it.peek(2) == '=' || it.peek(2) == '!'))
+			return true;
+		return false;
+	}
+
+	private static boolean isStartLookBehind(CharInspector it) {
+		final char current0 = it.peek(0);
+		if (current0 == '(' && it.peek(1) == '?' && it.peek(2) == '<' && (it.peek(3) == '=' || it.peek(3) == '!'))
+			return true;
+		return false;
+	}
+
 	private static boolean isStartOpenParenthesis(CharInspector it) {
 		final char current0 = it.peek(0);
 		if (current0 == '(')
@@ -109,10 +134,28 @@ public class RegexExpression {
 		return false;
 	}
 
+	private static boolean isStartPosixGroup(CharInspector it) {
+		final char current0 = it.peek(0);
+		if (current0 == '[' && it.peek(1) == '[' && it.peek(2) == ':')
+			return true;
+		return false;
+	}
+
 	private static boolean isStartNamedCapturingGroup(CharInspector it) {
 		final char current0 = it.peek(0);
-		if (current0 == '(' && it.peek(1) == '?' && it.peek(2) == '<')
+		if (current0 == '(' && it.peek(1) == '?' && it.peek(2) == '<') {
-			return true;
+			int i = 3;
+			while (it.peek(i) != 0) {
+				if (it.peek(i) == '>' && i == 3)
+					return false;
+				if (it.peek(i) == '>')
+					return true;
+				if (Character.isLetter(it.peek(i)) == false)
+					return false;
+				i++;
+			}
+
+		}
 		return false;
 	}
 
@@ -140,6 +183,23 @@ public class RegexExpression {
 		}
 	}
 
+	private static ReToken readLookAhead(CharInspector it) throws RegexParsingException {
+		it.jump();
+		it.jump();
+		final char ch = it.peek(0);
+		it.jump();
+		return new ReToken(ReTokenType.LOOK_AHEAD, "?" + ch);
+	}
+
+	private static ReToken readLookBehind(CharInspector it) throws RegexParsingException {
+		it.jump();
+		it.jump();
+		it.jump();
+		final char ch = it.peek(0);
+		it.jump();
+		return new ReToken(ReTokenType.LOOK_BEHIND, "?<" + ch);
+	}
+
 	private static ReToken readNamedGroup(CharInspector it) throws RegexParsingException {
 		it.jump();
 		it.jump();
@@ -218,6 +278,23 @@ public class RegexExpression {
 		return false;
 	}
 
+	private static String readGroupPosix(CharInspector it) {
+		it.jump();
+		it.jump();
+		it.jump();
+		final StringBuilder result = new StringBuilder(":");
+		while (it.peek(0) != 0) {
+			char ch = it.peek(0);
+			it.jump();
+			result.append(ch);
+			if (ch == ':')
+				break;
+		}
+		it.jump();
+		it.jump();
+		return result.toString();
+	}
+
 	private static String readGroup(CharInspector it) {
 		final char current0 = it.peek(0);
 		if (current0 != '[')

src/net/sourceforge/plantuml/regexdiagram/ShuntingYard.java

@@ -59,7 +59,7 @@ public class ShuntingYard {
 				ouputQueue.add(token);
 			} else if (token.getType() == ReTokenType.GROUP) {
 				ouputQueue.add(token);
-			} else if (token.getType() == ReTokenType.NAMED_GROUP) {
+			} else if (token.getType().isNamedGroupOrLookAheadOrLookBehind()) {
 				operatorStack.addFirst(token);
 			} else if (token.getType() == ReTokenType.CLASS) {
 				ouputQueue.add(token);
@@ -82,11 +82,9 @@ public class ShuntingYard {
 						&& operatorStack.peekFirst().getType() != ReTokenType.PARENTHESIS_OPEN)
 					ouputQueue.add(operatorStack.removeFirst());
 				final ReToken first = operatorStack.removeFirst();
-				if (operatorStack.peekFirst() != null
+				if (operatorStack.peekFirst() != null && operatorStack.peekFirst().getType().isNamedGroupOrLookAheadOrLookBehind())
-						&& operatorStack.peekFirst().getType() == ReTokenType.NAMED_GROUP)
 					ouputQueue.add(operatorStack.removeFirst());
 
-
 			} else {
 				throw new UnsupportedOperationException(token.toString());
 			}

src/net/sourceforge/plantuml/version/Version.java

@@ -46,7 +46,7 @@ public class Version {
 
 	// Warning, "version" should be the same in gradle.properties and Version.java
 	// Any idea anyone how to magically synchronize those :-) ?
-	private static final String version = "1.2023.14beta1";
+	private static final String version = "1.2023.14beta2";
 
 	public static String versionString() {
 		return version;