lib/bio/data/aa.rb in bio-1.4.3.0001 vs lib/bio/data/aa.rb in bio-1.5.0

@@ -106,27 +106,25 @@
       'W' => 204.23,
       'Y' => 181.19,
     }
 
     def weight(x = nil)
-      if x
-        if x.length > 1
-          total = 0.0
-          x.each_byte do |byte|
-            aa = byte.chr.upcase
-            if WEIGHT[aa]
-              total += WEIGHT[aa]
-            else
-              raise "Error: invalid amino acid '#{aa}'"
-            end
+      return WEIGHT unless x
+
+      if x.length > 1
+        total = 0.0
+        x.each_byte do |byte|
+          aa = byte.chr.upcase
+          if WEIGHT[aa]
+            total += WEIGHT[aa]
+          else
+            raise "Error: invalid amino acid '#{aa}'"
           end
-          total -= NucleicAcid.weight[:water] * (x.length - 1)
-        else
-          WEIGHT[x]
         end
+        total -= NucleicAcid.weight[:water] * (x.length - 1)
       else
-        WEIGHT
+        WEIGHT[x]
       end
     end
 
     def [](x)
       NAMES[x]
@@ -235,15 +233,11 @@
 
     private
 
 
     def reverse
-      hash = Hash.new
-      NAMES.each do |k, v|
-        hash[v] = k
-      end
-      hash
+      @reverse ||= NAMES.invert
     end
 
   end
 
 
@@ -251,21 +245,9 @@
   include Data
 
   # as class methods
   extend Data
 
-
-  private
-
-
-  # override when used as an instance method to improve performance
-  alias orig_reverse reverse
-  def reverse
-    unless @reverse
-      @reverse = orig_reverse
-    end
-    @reverse
-  end
 
 end
 
 end # module Bio