From 280b749e38cd5c3bcf598b3493563f92fdf7efb7 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Mon, 27 Sep 2021 21:29:44 -0400
Subject: [PATCH] Track Rule IDs

---
 lib/imbecile.rb             |  8 ++++----
 lib/imbecile/parser.rb      | 13 ++++---------
 lib/imbecile/parser/item.rb | 34 +++++++++++++++-------------------
 lib/imbecile/rule.rb        | 32 ++++++++++++++++++++++++++------
 4 files changed, 49 insertions(+), 38 deletions(-)

diff --git a/lib/imbecile.rb b/lib/imbecile.rb
index 3443fcf..6fdf234 100644
--- a/lib/imbecile.rb
+++ b/lib/imbecile.rb
@@ -81,8 +81,8 @@ class Imbecile
     elsif input.slice!(/\A(\S+)\s*:\s*\[(.*?)\] <<\n(.*?)^>>\n/m)
       rule_name, components, code = $1, $2, $3
       components = components.strip.split(/\s+/)
-      @rules[rule_name] ||= []
-      @rules[rule_name] << Rule.new(rule_name, components, code)
+      @rules[rule_name] ||= Rule.new(rule_name, @rules.size)
+      @rules[rule_name].add_pattern(components, code)
     else
       if input.size > 25
         input = input.slice(0..20) + "..."
@@ -106,8 +106,8 @@ class Imbecile
     unless @rules["Start"]
       raise Error.new("Start rule not found")
     end
-    @rules.each do |rule_name, rules|
-      rules.each do |rule|
+    @rules.each do |rule_name, rule|
+      rule.patterns.each do |rule|
         rule.components.map! do |component|
           if token_names[component]
             token_names[component]
diff --git a/lib/imbecile/parser.rb b/lib/imbecile/parser.rb
index 61f4046..d960011 100644
--- a/lib/imbecile/parser.rb
+++ b/lib/imbecile/parser.rb
@@ -6,9 +6,9 @@ class Imbecile
       @token_eof = Token.new("$", nil, TOKEN_EOF)
       @item_sets = []
       @item_sets_set = {}
-      start_items = rules["Start"].map do |rule|
-        rule.components << @token_eof
-        Item.new(rule, 0)
+      start_items = rules["Start"].patterns.map do |pattern|
+        pattern.components << @token_eof
+        Item.new(pattern, 0)
       end
       eval_item_sets = Set.new
       eval_item_sets << ItemSet.new(start_items)
@@ -40,12 +40,7 @@ class Imbecile
         end
         puts item_set
         item_set.follow_item_set.each do |follow_symbol, follow_item_set|
-          if follow_symbol.is_a?(Token)
-            name = follow_symbol.name
-          else
-            name = follow_symbol[0].name
-          end
-          puts " #{name} => #{follow_item_set.id}"
+          puts " #{follow_symbol.name} => #{follow_item_set.id}"
         end
         puts
       end
diff --git a/lib/imbecile/parser/item.rb b/lib/imbecile/parser/item.rb
index b1ea61c..6ca5e00 100644
--- a/lib/imbecile/parser/item.rb
+++ b/lib/imbecile/parser/item.rb
@@ -3,24 +3,24 @@ class Imbecile
 
     class Item
 
-      attr_reader :rule
+      attr_reader :pattern
       attr_reader :position
 
-      def initialize(rule, position)
-        @rule = rule
+      def initialize(pattern, position)
+        @pattern = pattern
         @position = position
       end
 
       def next_component
-        @rule.components[@position]
+        @pattern.components[@position]
       end
 
       def hash
-        [@rule, @position].hash
+        [@pattern, @position].hash
       end
 
       def ==(other)
-        @rule == other.rule && @position == other.position
+        @pattern == other.pattern && @position == other.position
       end
 
       def eql?(other)
@@ -28,9 +28,9 @@ class Imbecile
       end
 
       def closed_items
-        if @rule.components[@position].is_a?(Array)
-          @rule.components[@position].map do |rule|
-            Item.new(rule, 0)
+        if @pattern.components[@position].is_a?(Rule)
+          @pattern.components[@position].patterns.map do |pattern|
+            Item.new(pattern, 0)
           end
         else
           []
@@ -38,7 +38,7 @@ class Imbecile
       end
 
       def follow_symbol
-        @rule.components[@position]
+        @pattern.components[@position]
       end
 
       def followed_by?(symbol)
@@ -46,25 +46,21 @@ class Imbecile
       end
 
       def next_position
-        Item.new(@rule, @position + 1)
+        Item.new(@pattern, @position + 1)
       end
 
       def to_s
         parts = []
-        @rule.components.each_with_index do |symbol, index|
+        @pattern.components.each_with_index do |symbol, index|
           if @position == index
             parts << "."
           end
-          if symbol.is_a?(Token)
-            parts << symbol.name
-          else
-            parts << symbol[0].name
-          end
+          parts << symbol.name
         end
-        if @position == @rule.components.size
+        if @position == @pattern.components.size
           parts << "."
         end
-        "#{@rule.name} -> #{parts.join(" ")}"
+        "#{@pattern.rule.name} -> #{parts.join(" ")}"
       end
 
     end
diff --git a/lib/imbecile/rule.rb b/lib/imbecile/rule.rb
index 42d1be2..f0e2687 100644
--- a/lib/imbecile/rule.rb
+++ b/lib/imbecile/rule.rb
@@ -2,16 +2,36 @@ class Imbecile
 
   class Rule
 
+    class Pattern
+
+      attr_reader :rule
+
+      attr_reader :components
+
+      attr_reader :code
+
+      def initialize(rule, components, code)
+        @rule = rule
+        @components = components
+        @code = code
+      end
+
+    end
+
+    attr_reader :id
+
     attr_reader :name
 
-    attr_reader :components
+    attr_reader :patterns
 
-    attr_reader :code
-
-    def initialize(name, components, code)
+    def initialize(name, id)
       @name = name
-      @components = components
-      @code = code
+      @id = id
+      @patterns = []
+    end
+
+    def add_pattern(components, code)
+      @patterns << Pattern.new(self, components, code)
     end
 
   end