Merge pull request #354 from ydah/refactor

Refactor to simplify the code

lib/lrama/context.rb

@@ -41,7 +41,7 @@ def yysymbol_kind_t
     def yyfinal
       @states.states.find do |state|
         state.items.find do |item|
-          item.rule.lhs.accept_symbol? && item.end_of_rule?
+          item.lhs.accept_symbol? && item.end_of_rule?
         end
       end.id
     end

lib/lrama/grammar.rb

@@ -243,7 +243,7 @@ def nterms
     def compute_nullable
       @rules.each do |rule|
         case
-        when rule.rhs.empty?
+        when rule.empty_rule?
           rule.nullable = true
         when rule.rhs.any?(&:term)
           rule.nullable = false

lib/lrama/grammar/rule.rb

@@ -19,15 +19,15 @@ def ==(other)
       # TODO: Change this to display_name
       def to_s
         l = lhs.id.s_value
-        r = rhs.empty? ? "ε" : rhs.map {|r| r.id.s_value }.join(", ")
+        r = empty_rule? ? "ε" : rhs.map {|r| r.id.s_value }.join(", ")
 
         "#{l} -> #{r}"
       end
 
       # Used by #user_actions
       def as_comment
         l = lhs.id.s_value
-        r = rhs.empty? ? "%empty" : rhs.map(&:display_name).join(" ")
+        r = empty_rule? ? "%empty" : rhs.map(&:display_name).join(" ")
 
         "#{l}: #{r}"
       end

lib/lrama/states/item.rb

@@ -5,7 +5,7 @@ class States
     class Item < Struct.new(:rule, :position, keyword_init: true)
       # Optimization for States#setup_state
       def hash
-        [rule.id, position].hash
+        [rule_id, position].hash
       end
 
       def rule_id
@@ -17,62 +17,66 @@ def empty_rule?
       end
 
       def number_of_rest_symbols
-        rule.rhs.count - position
+        rhs.count - position
       end
 
       def lhs
         rule.lhs
       end
 
+      def rhs
+        rule.rhs
+      end
+
       def next_sym
-        rule.rhs[position]
+        rhs[position]
       end
 
       def next_next_sym
-        rule.rhs[position + 1]
+        rhs[position + 1]
       end
 
       def previous_sym
-        rule.rhs[position - 1]
+        rhs[position - 1]
       end
 
       def end_of_rule?
-        rule.rhs.count == position
+        rhs.count == position
       end
 
       def beginning_of_rule?
         position == 0
       end
 
       def start_item?
-        rule.id == 0 && position == 0
+        rule.initial_rule? && beginning_of_rule?
       end
 
       def new_by_next_position
         Item.new(rule: rule, position: position + 1)
       end
 
       def symbols_before_dot
-        rule.rhs[0...position]
+        rhs[0...position]
       end
 
       def symbols_after_dot
-        rule.rhs[position..-1]
+        rhs[position..-1]
       end
 
       def to_s
         "#{lhs.id.s_value}: #{display_name}"
       end
 
       def display_name
-        r = rule.rhs.map(&:display_name).insert(position, "•").join(" ")
-        "#{r}  (rule #{rule.id})"
+        r = rhs.map(&:display_name).insert(position, "•").join(" ")
+        "#{r}  (rule #{rule_id})"
       end
 
       # Right after position
       def display_rest
-        r = rule.rhs[position..-1].map(&:display_name).join(" ")
-        ". #{r}  (rule #{rule.id})"
+        r = rhs[position..-1].map(&:display_name).join(" ")
+        ". #{r}  (rule #{rule_id})"
       end
     end
   end

lib/lrama/states_reporter.rb

@@ -53,7 +53,7 @@ def report_grammar(io)
       last_lhs = nil
 
       @states.rules.each do |rule|
-        if rule.rhs.empty?
+        if rule.empty_rule?
           r = "ε"
         else
           r = rule.rhs.map(&:display_name).join(" ")
@@ -84,17 +84,15 @@ def report_states(io, itemsets, lookaheads, solved, counterexamples, verbose)
         last_lhs = nil
         list = itemsets ? state.items : state.kernels
         list.sort_by {|i| [i.rule_id, i.position] }.each do |item|
-          rule = item.rule
-          position = item.position
-          if rule.rhs.empty?
+          if item.empty_rule?
             r = "ε •"
           else
-            r = rule.rhs.map(&:display_name).insert(position, "•").join(" ")
+            r = item.rhs.map(&:display_name).insert(item.position, "•").join(" ")
           end
-          if rule.lhs == last_lhs
-            l = " " * rule.lhs.id.s_value.length + "|"
+          if item.lhs == last_lhs
+            l = " " * item.lhs.id.s_value.length + "|"
           else
-            l = rule.lhs.id.s_value + ":"
+            l = item.lhs.id.s_value + ":"
           end
           la = ""
           if lookaheads && item.end_of_rule?
@@ -104,9 +102,9 @@ def report_states(io, itemsets, lookaheads, solved, counterexamples, verbose)
               la = "  [#{look_ahead.map(&:display_name).join(", ")}]"
             end
           end
-          last_lhs = rule.lhs
+          last_lhs = item.lhs
 
-          io << sprintf("%5i %s %s%s\n", rule.id, l, r, la)
+          io << sprintf("%5i %s %s%s\n", item.rule_id, l, r, la)
         end
         io << "\n"