diff --git a/lib/yawpa.rb b/lib/yawpa.rb
index 321a9f5..8dbf696 100644
--- a/lib/yawpa.rb
+++ b/lib/yawpa.rb
@@ -17,11 +17,29 @@ module Yawpa
     i = 0
     while i < params.length
       param = params[i]
-      if param[0] != '-'
-        args << params[i]
+      if param =~ /^(-+)(.+)$/
+        case $1.length
+        when 2
+          param_key = if options[$2]
+                        $2
+                      elsif options[$2.to_sym]
+                        $2.to_sym
+                      else
+                        nil
+                      end
+          if param_key.nil?
+            raise UnknownOptionException.new("Unknown option '#{param}'")
+          end
+          opt_config = options[param_key]
+          nargs = opt_config[:nargs] || 0
+          if nargs == 0
+            opts[param_key] = true
+          elsif nargs.class == FixNum
+          elsif nargs.class == Range
+          end
+        end
       else
-        opt_config = options[param] || options[param.to_sym]
-        raise UnknownOptionException.new("Unknown option '#{param}'") if opt_config.nil?
+        args << params[i]
       end
       i += 1
     end
diff --git a/spec/yawpa_spec.rb b/spec/yawpa_spec.rb
index 5a0ae80..18b310a 100644
--- a/spec/yawpa_spec.rb
+++ b/spec/yawpa_spec.rb
@@ -15,5 +15,19 @@ describe Yawpa do
       params = ['one', '--option', 'two']
       expect { Yawpa.parse(params, options) }.to raise_error
     end
+
+    it "returns boolean options which are set" do
+      options = {
+        one: {},
+        two: {},
+        three: {},
+      }
+      params = ['--one', 'arg', '--two', 'arg2']
+      opts, args = Yawpa.parse(params, options)
+      opts.include?(:one).should be_true
+      opts.include?(:two).should be_true
+      opts.include?(:three).should be_false
+      args.should eq(['arg', 'arg2'])
+    end
   end
 end