lib/dentaku/calculator.rb in dentaku-1.0.0 vs lib/dentaku/calculator.rb in dentaku-1.1.0

@@ -1,9 +1,9 @@
 require 'dentaku/evaluator'
+require 'dentaku/expression'
 require 'dentaku/rules'
 require 'dentaku/token'
-require 'dentaku/tokenizer'
 
 module Dentaku
   class Calculator
     attr_reader :result
 
@@ -20,23 +20,24 @@
       fns.each { |fn| Rules.add_function(fn) }
       self
     end
 
     def evaluate(expression, data={})
-      @tokenizer ||= Tokenizer.new
-      @tokens = @tokenizer.tokenize(expression)
+      evaluate!(expression, data)
+    rescue UnboundVariableError
+      yield expression if block_given?
+    end
 
+    def evaluate!(expression, data={})
       store(data) do
+        expr = Expression.new(expression, @memory)
+        raise UnboundVariableError.new(expr.identifiers) if expr.unbound?
         @evaluator ||= Evaluator.new
-        @result = @evaluator.evaluate(replace_identifiers_with_values)
+        @result = @evaluator.evaluate(expr.tokens)
       end
     end
 
-    def memory(key=nil)
-      key ? @memory[key.to_sym] : @memory
-    end
-
     def store(key_or_hash, value=nil)
       restore = @memory.dup
 
       if value
         @memory[key_or_hash.to_sym] = value
@@ -60,31 +61,8 @@
       @memory = {}
     end
 
     def empty?
       @memory.empty?
-    end
-
-    private
-
-    def replace_identifiers_with_values
-      @tokens.map do |token|
-        if token.is?(:identifier)
-          value = memory(token.value)
-          type  = type_for_value(value)
-
-          Token.new(type, value)
-        else
-          token
-        end
-      end
-    end
-
-    def type_for_value(value)
-      case value
-      when String then :string
-      when TrueClass, FalseClass then :logical
-      else :numeric
-      end
     end
   end
 end