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[toc] / antlr4-cpp-runtime-4.9.2-source / runtime / src / atn / EmptyPredictionContext.cpp

diff --git a/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/EmptyPredictionContext.cpp b/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/EmptyPredictionContext.cpp
new file mode 100644 (file)
index 0000000..17223bf
--- /dev/null
+++ b/antlr4-cpp-runtime-4.9.2-source/runtime/src/atn/EmptyPredictionContext.cpp
@@ -0,0 +1,35 @@
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#include "atn/EmptyPredictionContext.h"
+
+using namespace antlr4::atn;
+
+EmptyPredictionContext::EmptyPredictionContext() : SingletonPredictionContext(nullptr, EMPTY_RETURN_STATE) {
+}
+
+bool EmptyPredictionContext::isEmpty() const {
+  return true;
+}
+
+size_t EmptyPredictionContext::size() const {
+  return 1;
+}
+
+Ref<PredictionContext> EmptyPredictionContext::getParent(size_t /*index*/) const {
+  return nullptr;
+}
+
+size_t EmptyPredictionContext::getReturnState(size_t /*index*/) const {
+  return returnState;
+}
+
+bool EmptyPredictionContext::operator == (const PredictionContext &o) const {
+  return this == &o;
+}
+
+std::string EmptyPredictionContext::toString() const {
+  return "$";
+}