remember to commit the example source

Author: Hal Finkel

clang/examples/PrintTokensSyntax/CMakeLists.txt

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+add_llvm_library(PrintTokensSyntax MODULE PrintTokensSyntax.cpp PLUGIN_TOOL clang)
+
+if(LLVM_ENABLE_PLUGINS)
+  set(LLVM_LINK_COMPONENTS
+    Support
+  )
+  clang_target_link_libraries(PrintTokensSyntax PRIVATE
+    clangAST
+    clangBasic
+    clangParse
+    clangLex
+    )
+endif()

clang/examples/PrintTokensSyntax/PrintTokensSyntax.cpp

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+//===- PrintTokensSyntax.cpp ----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Example clang syntax plugin which enables the printing of all tokens in a
+// function body.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Parse/Parser.h"
+using namespace clang;
+
+namespace {
+
+class PrintTokensHandler : public SyntaxHandler {
+public:
+  PrintTokensHandler() : SyntaxHandler("tokens") { }
+
+  void GetReplacement(Preprocessor &PP, Declarator &D,
+                      CachedTokens &Toks,
+                      llvm::raw_string_ostream &OS) override {
+    for (auto &Tok : Toks) {
+      OS << "printf(\"%s\\n\", \"";
+      OS.write_escaped(PP.getSpelling(Tok));
+      OS << "\");\n";
+    }
+  }
+
+  void AddToPredefines(llvm::raw_string_ostream &OS) override {
+    OS << "#include <stdio.h>\n";
+  }
+};
+
+}
+
+static SyntaxHandlerRegistry::Add<PrintTokensHandler>
+X("tokens", "collect all tokens");
+