generator.rb in rantly-1.2.0

- old
+ new

@@ -40,11 +40,11 @@
     def tries
       @nfailed
     end
 
     def to_s
-      "Exceed gen limit #{@limit}: #{@nfailed} failed guards)"
+      "Exceed gen limit #{@limit}: #{@nfailed} failed guards"
     end
   end
 
   # limit attempts to 10 times of how many things we want to generate
   def each(n,limit=10,&block)
@@ -119,11 +119,11 @@
     @size = old_size
     return r
   end
 
   # wanna avoid going into Bignum when calling range with these.
-  INTEGER_MAX = (2**(0.size * 8 -2) -1) / 2
+  INTEGER_MAX = (2**(0.size * 8 - 2) - 1) / 2
   INTEGER_MIN = -(INTEGER_MAX)
   def integer(limit=nil)
     case limit
     when Range
       hi = limit.end
@@ -139,12 +139,22 @@
 
   def positive_integer
     range(0)
   end
 
-  def float
-    rand
+  def float(distribution=nil, params={})
+    case distribution
+    when :normal
+      params[:center] ||= 0
+      params[:scale] ||= 1
+      raise "The distribution scale should be greater than zero" unless params[:scale] > 0
+      # Sum of 6 draws from a uniform distribution give as a draw of a normal
+      # distribution centered in 3 (central limit theorem).
+      ([rand, rand, rand, rand, rand, rand].reduce(0, :+) - 3) * params[:scale] + params[:center]
+    else
+      rand
+    end
   end
 
   def range(lo=nil,hi=nil)
     lo ||= INTEGER_MIN
     hi ||= INTEGER_MAX
@@ -228,22 +238,22 @@
       def of(regexp)
         ASCII.scan(regexp).to_a.map! { |char| char[0].ord }
       end
     end
 
-    ALNUM = Chars.of /[[:alnum:]]/
-    ALPHA = Chars.of /[[:alpha:]]/
-    BLANK = Chars.of /[[:blank:]]/
-    CNTRL = Chars.of /[[:cntrl:]]/
-    DIGIT = Chars.of /[[:digit:]]/
-    GRAPH = Chars.of /[[:graph:]]/
-    LOWER = Chars.of /[[:lower:]]/
-    PRINT = Chars.of /[[:print:]]/
-    PUNCT = Chars.of /[[:punct:]]/
-    SPACE = Chars.of /[[:space:]]/
-    UPPER = Chars.of /[[:upper:]]/
-    XDIGIT = Chars.of /[[:xdigit:]]/
-    ASCII = Chars.of /./
+    ALNUM = Chars.of(/[[:alnum:]]/)
+    ALPHA = Chars.of(/[[:alpha:]]/)
+    BLANK = Chars.of(/[[:blank:]]/)
+    CNTRL = Chars.of(/[[:cntrl:]]/)
+    DIGIT = Chars.of(/[[:digit:]]/)
+    GRAPH = Chars.of(/[[:graph:]]/)
+    LOWER = Chars.of(/[[:lower:]]/)
+    PRINT = Chars.of(/[[:print:]]/)
+    PUNCT = Chars.of(/[[:punct:]]/)
+    SPACE = Chars.of(/[[:space:]]/)
+    UPPER = Chars.of(/[[:upper:]]/)
+    XDIGIT = Chars.of(/[[:xdigit:]]/)
+    ASCII = Chars.of(/./)
 
 
     CLASSES = {
       :alnum => ALNUM,
       :alpha => ALPHA,