From cc8877d26f7f55ffb92890f74f09e5b28e4416e2 Mon Sep 17 00:00:00 2001
From: ydah <13041216+ydah@users.noreply.github.com>
Date: Sat, 4 Nov 2023 16:53:40 +0900
Subject: [PATCH] Implement parameterizing rules for list

---
 lib/lrama/grammar.rb     | 7 +++++++
 lib/lrama/lexer.rb       | 2 +-
 lib/lrama/lexer/token.rb | 1 +
 parser.y                 | 5 +++++
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/lib/lrama/grammar.rb b/lib/lrama/grammar.rb
index 609be70e..652abbba 100644
--- a/lib/lrama/grammar.rb
+++ b/lib/lrama/grammar.rb
@@ -578,6 +578,13 @@ def normalize_rules
           @rules << Rule.new(id: @rules.count, lhs: lhs, rhs: [nonempty_list_token], code: c, precedence_sym: precedence_sym, lineno: lineno)
           @rules << Rule.new(id: @rules.count, lhs: nonempty_list_token, rhs: [token], code: c, precedence_sym: precedence_sym, lineno: lineno)
           @rules << Rule.new(id: @rules.count, lhs: nonempty_list_token, rhs: [nonempty_list_token, token], code: c, precedence_sym: precedence_sym, lineno: lineno)
+        elsif rhs2.any? {|r| r.type == Token::List }
+          list_token = Token.new(type: Token::Ident, s_value: "list_#{rhs2[0].s_value}")
+          token = Token.new(type: Token::Ident, s_value: rhs2[0].s_value)
+          add_term(id: list_token)
+          @rules << Rule.new(id: @rules.count, lhs: lhs, rhs: [list_token], code: c, precedence_sym: precedence_sym, lineno: lineno)
+          @rules << Rule.new(id: @rules.count, lhs: list_token, rhs: [], code: c, precedence_sym: precedence_sym, lineno: lineno)
+          @rules << Rule.new(id: @rules.count, lhs: list_token, rhs: [list_token, token], code: c, precedence_sym: precedence_sym, lineno: lineno)
         else
           @rules << Rule.new(id: @rules.count, lhs: lhs, rhs: rhs2, code: c, precedence_sym: precedence_sym, lineno: lineno)
         end
diff --git a/lib/lrama/lexer.rb b/lib/lrama/lexer.rb
index 6d9d21fb..970d4566 100644
--- a/lib/lrama/lexer.rb
+++ b/lib/lrama/lexer.rb
@@ -79,7 +79,7 @@ def lex_token
         return [@scanner.matched, @scanner.matched]
       when @scanner.scan(/#{PERCENT_TOKENS.join('|')}/)
         return [@scanner.matched, @scanner.matched]
-      when @scanner.scan(/[\?\+]/)
+      when @scanner.scan(/[\?\+\*]/)
         return [@scanner.matched, @scanner.matched]
       when @scanner.scan(/<\w+>/)
         return [:TAG, build_token(type: Token::Tag, s_value: @scanner.matched)]
diff --git a/lib/lrama/lexer/token.rb b/lib/lrama/lexer/token.rb
index b30d087a..67e01734 100644
--- a/lib/lrama/lexer/token.rb
+++ b/lib/lrama/lexer/token.rb
@@ -37,6 +37,7 @@ def self.define_type(name)
       define_type(:Char)             # '+'
       define_type(:Option)           # actual?
       define_type(:Nonempty_list)    # actual+
+      define_type(:List)             # actual*
     end
   end
 end
diff --git a/parser.y b/parser.y
index e2a94745..f6bed361 100644
--- a/parser.y
+++ b/parser.y
@@ -304,6 +304,11 @@ rule
             token = Token.new(type: Token::Nonempty_list, s_value: val[1])
             result = val[0].append(token)
           }
+     | rhs "*"
+          {
+             token = Token.new(type: Token::List, s_value: val[1])
+             result = val[0].append(token)
+          }
      | rhs "{"
          {
            if @prec_seen