1 files changed, 66 insertions, 0 deletions
diff --git a/Source/cmGeneratorExpressionLexer.cxx b/Source/cmGeneratorExpressionLexer.cxx
new file mode 100644
index 0000000..931fd4d
--- /dev/null
+++ b/Source/cmGeneratorExpressionLexer.cxx
@@ -0,0 +1,66 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmGeneratorExpressionLexer.h"
+
+cmGeneratorExpressionLexer::cmGeneratorExpressionLexer()
+  : SawBeginExpression(false)
+  , SawGeneratorExpression(false)
+{
+}
+
+static void InsertText(const char* upto, const char* c,
+                       std::vector<cmGeneratorExpressionToken>& result)
+{
+  if (upto != c) {
+    result.push_back(cmGeneratorExpressionToken(
+      cmGeneratorExpressionToken::Text, upto, c - upto));
+  }
+}
+
+std::vector<cmGeneratorExpressionToken> cmGeneratorExpressionLexer::Tokenize(
+  const std::string& input)
+{
+  std::vector<cmGeneratorExpressionToken> result;
+
+  const char* c = input.c_str();
+  const char* upto = c;
+
+  for (; *c; ++c) {
+    switch (*c) {
+      case '$':
+        if (c[1] == '<') {
+          InsertText(upto, c, result);
+          result.push_back(cmGeneratorExpressionToken(
+            cmGeneratorExpressionToken::BeginExpression, c, 2));
+          upto = c + 2;
+          ++c;
+          SawBeginExpression = true;
+        }
+        break;
+      case '>':
+        InsertText(upto, c, result);
+        result.push_back(cmGeneratorExpressionToken(
+          cmGeneratorExpressionToken::EndExpression, c, 1));
+        upto = c + 1;
+        SawGeneratorExpression = SawBeginExpression;
+        break;
+      case ':':
+        InsertText(upto, c, result);
+        result.push_back(cmGeneratorExpressionToken(
+          cmGeneratorExpressionToken::ColonSeparator, c, 1));
+        upto = c + 1;
+        break;
+      case ',':
+        InsertText(upto, c, result);
+        result.push_back(cmGeneratorExpressionToken(
+          cmGeneratorExpressionToken::CommaSeparator, c, 1));
+        upto = c + 1;
+        break;
+      default:
+        break;
+    }
+  }
+  InsertText(upto, c, result);
+
+  return result;
+}