lib/sxp/reader/scheme.rb in sxp-0.0.5 vs lib/sxp/reader/scheme.rb in sxp-0.0.6

@@ -1,17 +1,29 @@
 module SXP; class Reader
   ##
-  # A Scheme-like S-expression parser.
+  # A Scheme R4RS S-expressions parser.
+  #
+  # @see http://people.csail.mit.edu/jaffer/r4rs_9.html#SEC65
   class Scheme < Extended
     DECIMAL         = /^[+-]?(\d*)?\.\d*$/.freeze
     INTEGER_BASE_2  = /^[+-]?[01]+$/.freeze
     INTEGER_BASE_8  = /^[+-]?[0-7]+$/.freeze
     INTEGER_BASE_10 = /^[+-]?\d+$/.freeze
     INTEGER_BASE_16 = /^[+-]?[\da-z]+$/i.freeze
     RATIONAL        = /^([+-]?\d+)\/(\d+)$/.freeze
 
     ##
+    # Initializes the reader.
+    #
+    # @param  [IO, StringIO, String]   input
+    # @param  [Hash{Symbol => Object}] options
+    # @option options [Symbol]         :version (:r4rs)
+    def initialize(input, options = {}, &block)
+      super(input, {:version => :r4rs}.merge(options), &block)
+    end
+
+    ##
     # @return [Object]
     def read_token
       case peek_char
         when ?# then [:atom, read_sharp]
         else super
@@ -33,20 +45,20 @@
     ##
     # @return [Object]
     def read_sharp
       skip_char # '#'
       case char = read_char
-        when ?n  then nil    # not in Scheme
-        when ?f  then false
-        when ?t  then true
-        when ?b  then read_integer(2)
-        when ?o  then read_integer(8)
-        when ?d  then read_integer(10)
-        when ?x  then read_integer(16)
-        when ?\\ then read_character
-        when ?;  then skip; read
-        when ?!  then skip_line; read # shebang
+        when ?n, ?N  then nil    # not in Scheme per se
+        when ?f, ?F  then false
+        when ?t, ?T  then true
+        when ?b, ?B  then read_integer(2)
+        when ?o, ?O  then read_integer(8)
+        when ?d, ?D  then read_integer(10)
+        when ?x, ?X  then read_integer(16)
+        when ?\\     then read_character
+        when ?;      then skip; read
+        when ?!      then skip_line; read # shebang
         else raise Error, "invalid sharp-sign read syntax: ##{char.chr}"
       end
     end
-  end # class Reader
+  end # class Scheme
 end; end # class SXP::Reader