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diff --git a/tool/src/org/antlr/v4/codegen/model/SemPred.java b/tool/src/org/antlr/v4/codegen/model/SemPred.java
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+/*
+ * [The "BSD license"]
+ *  Copyright (c) 2012 Terence Parr
+ *  Copyright (c) 2012 Sam Harwell
+ *  All rights reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions
+ *  are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.antlr.v4.codegen.model;
+
+import org.antlr.v4.codegen.ActionTranslator;
+import org.antlr.v4.codegen.CodeGenerator;
+import org.antlr.v4.codegen.OutputModelFactory;
+import org.antlr.v4.codegen.model.chunk.ActionChunk;
+import org.antlr.v4.runtime.atn.AbstractPredicateTransition;
+import org.antlr.v4.tool.ast.ActionAST;
+import org.antlr.v4.tool.ast.GrammarAST;
+
+import java.util.List;
+
+/** */
+public class SemPred extends Action {
+	/**
+	 * The user-specified terminal option {@code fail}, if it was used and the
+	 * value is a string literal. For example:
+	 *
+	 * <p>
+	 * {@code {pred}?<fail='message'>}</p>
+	 */
+	public String msg;
+	/**
+	 * The predicate string with <code>{</code> and <code>}?</code> stripped from the ends.
+	 */
+	public String predicate;
+
+	/**
+	 * The translated chunks of the user-specified terminal option {@code fail},
+	 * if it was used and the value is an action. For example:
+	 *
+	 * <p>
+	 * {@code {pred}?<fail={"Java literal"}>}</p>
+	 */
+	@ModelElement public List<ActionChunk> failChunks;
+
+	public SemPred(OutputModelFactory factory, ActionAST ast) {
+		super(factory,ast);
+
+		assert ast.atnState != null
+			&& ast.atnState.getNumberOfTransitions() == 1
+			&& ast.atnState.transition(0) instanceof AbstractPredicateTransition;
+
+		GrammarAST failNode = ast.getOptionAST("fail");
+		CodeGenerator gen = factory.getGenerator();
+		predicate = ast.getText();
+		if (predicate.startsWith("{") && predicate.endsWith("}?")) {
+			predicate = predicate.substring(1, predicate.length() - 2);
+		}
+		predicate = gen.getTarget().getTargetStringLiteralFromString(predicate);
+
+		if ( failNode==null ) return;
+
+		if ( failNode instanceof ActionAST ) {
+			ActionAST failActionNode = (ActionAST)failNode;
+			RuleFunction rf = factory.getCurrentRuleFunction();
+			failChunks = ActionTranslator.translateAction(factory, rf,
+														  failActionNode.token,
+														  failActionNode);
+		}
+		else {
+			msg = gen.getTarget().getTargetStringLiteralFromANTLRStringLiteral(gen,
+																		  failNode.getText(),
+																		  true);
+		}
+	}
+}