Provide matched text to lexer user code block

assets/parser.d.erb

@@ -186,11 +186,12 @@ class <%= @classname %>
          * Execute user code associated with a lexer pattern.
          *
          * @param code_id The ID of the user code block to execute.
+         * @param match Matched text for this pattern.
          *
          * @return Token ID to accept, or _TOKEN_COUNT if the user code does
          *   not explicitly return a token.
          */
-        private uint user_code(uint code_id)
+        private uint user_code(uint code_id, string match)
         {
             switch (code_id)
             {
@@ -268,7 +269,7 @@ class <%= @classname %>
                     uint token_to_accept = longest_match_info.token;
                     if (longest_match_info.code_id != 0xFFFF_FFFFu)
                     {
-                        uint user_code_token = user_code(longest_match_info.code_id);
+                        uint user_code_token = user_code(longest_match_info.code_id, m_input[m_input_position..(m_input_position + longest_match_info.length)]);
                         /* A return of _TOKEN_COUNT from user_code() means
                          * that the user code did not explicitly return a
                          * token. So only override the token to return if the

spec/propane_spec.rb

@@ -300,4 +300,21 @@ EOF
     expect(results.status).to_not eq 0
     expect(results.stderr).to match %r{reduce/reduce conflict.*\(E\).*\(F\)}
   end
+
+  it "provides matched text to user code blocks" do
+    write_grammar <<EOF
+token id /[a-zA-Z_][a-zA-Z0-9_]*/ <<
+  writeln("Matched token is ", match);
+>>
+Start -> id;
+EOF
+    build_parser
+    compile("spec/test_lexer_match_text.d")
+    results = run
+    expect(results.status).to eq 0
+    verify_lines(results.stdout, [
+      "Matched token is identifier_123",
+      "pass1",
+    ])
+  end
 end

spec/test_lexer_match_text.d

@@ -0,0 +1,15 @@
+import testparser;
+import std.stdio;
+
+int main()
+{
+    return 0;
+}
+
+unittest
+{
+    string input = `identifier_123`;
+    auto parser = new Testparser.Parser(input);
+    assert(parser.parse() == true);
+    writeln("pass1");
+}