Ruby: add step6_file

1 files changed, 4 insertions, 1 deletions

diff --git a/ruby/reader.rb b/ruby/reader.rb
index 0c113e3..eddb319 100644
--- a/ruby/reader.rb
+++ b/ruby/reader.rb
@@ -17,7 +17,9 @@ end
 
 def tokenize(str)
     re = /[\s,]*(~@|[\[\]{}()'`~^@]|"(?:\\.|[^\\"])*"|;.*|[^\s\[\]{}('"`,;)]*)/
-    return str.scan(re).map{|m| m[0]}.select{|m| m != ""}
+    return str.scan(re).map{|m| m[0]}.select{ |t|
+        t != "" && t[0..0] != ";"
+    }
 end
 
 def parse_str(t)
@@ -69,6 +71,7 @@ end
 
 def read_str(str)
     tokens = tokenize(str)
+    return nil if tokens.size == 0
     return read_form(Reader.new(tokens))
 end