diff --git a/lib/yawpa.rb b/lib/yawpa.rb
index ea8b1a2..385d4b7 100644
--- a/lib/yawpa.rb
+++ b/lib/yawpa.rb
@@ -13,179 +13,190 @@ require "yawpa/version"
 # - Options can be defined with a range specifying the allowed number of
 #   parameters
 module Yawpa
+
   # Exception class raised when an unknown option is observed.
   class ArgumentParsingException < Exception; end
 
-  # Parse input parameters looking for options according to rules given in
-  # flags.
-  # Syntax:
-  #   opts, args = parse(params, options, flags = {})
-  #
-  # An ArgumentParsingException will be raised if an unknown option is observed
-  # or insufficient arguments are present for an option.
-  #
-  # Example +options+:
-  #
-  #   {
-  #     version: nil,
-  #     verbose: {short: 'v'},
-  #     server: {nargs: (1..2)},
-  #     username: {nargs: 1},
-  #     password: {nargs: 1},
-  #     color: :boolean,
-  #   }
-  #
-  # The keys of the +options+ Hash can be either strings or symbols.
-  #
-  #
-  # @param params [Array]
-  #   List of program parameters to parse.
-  # @param options [Hash]
-  #   Hash containing the long option names as keys, and values containing
-  #   special flags for the options as values (examples above).
-  #   Possible values:
-  #   +nil+:: No special flags for this option (equivalent to +{}+)
-  #   +:boolean+::
-  #     The option is a toggleable boolean option (equivalent to
-  #     +{boolean: true}+)
-  #   Hash::
-  #     Possible option flags:
-  #     - +:short+: specify a short option letter to associate with the long option
-  #     - +:nargs+: specify an exact number or range of possible numbers of
-  #       arguments to the option
-  #     - +:boolean+: if true, specify that the option is a toggleable boolean
-  #       option and allow a prefix of "no" to turn it off.
-  # @param flags [Hash]
-  #   Optional flags dictating how {.parse} should do its job.
-  # @option flags [Boolean] :posix_order
-  #   Stop processing parameters when a non-option argument is seen.
-  #   Set this to +true+ if you want to implement subcommands.
-  #
-  # @return [Array]
-  #   Two-element array containing +opts+ and +args+ return values.
-  #   +opts+::
-  #     The returned +opts+ value will be a Hash with the observed
-  #     options as keys and any option arguments as values.
-  #   +args+::
-  #     The returned +args+ will be an Array of the unprocessed
-  #     parameters (if +:posix_order+ was passed in +flags+, this array might
-  #     contain further options that were not processed after observing a
-  #     non-option parameters).
-  def self.parse(params, options, flags = {})
-    options = _massage_options(options)
-    opts = {}
-    args = []
-    i = 0
-    while i < params.length
-      param = params[i]
-      if param =~ /^--([^=]+)(?:=(.+))?$/
-        param_name, val = $1, $2
-        bool_val = true
-        if options[param_name].nil?
-          if param_name =~ /^no(.*)$/
-            test_param_name = $1
-            if options[test_param_name]
-              param_name = test_param_name
-              bool_val = false
+  class << self
+
+    # Parse input parameters looking for options according to rules given in
+    # flags.
+    # Syntax:
+    #   opts, args = parse(params, options, flags = {})
+    #
+    # An ArgumentParsingException will be raised if an unknown option is
+    # observed or insufficient arguments are present for an option.
+    #
+    # Example +options+:
+    #
+    #   {
+    #     version: nil,
+    #     verbose: {short: 'v'},
+    #     server: {nargs: (1..2)},
+    #     username: {nargs: 1},
+    #     password: {nargs: 1},
+    #     color: :boolean,
+    #   }
+    #
+    # The keys of the +options+ Hash can be either strings or symbols.
+    #
+    #
+    # @param params [Array]
+    #   List of program parameters to parse.
+    # @param options [Hash]
+    #   Hash containing the long option names as keys, and values containing
+    #   special flags for the options as values (examples above).
+    #   Possible values:
+    #   +nil+:: No special flags for this option (equivalent to +{}+)
+    #   +:boolean+::
+    #     The option is a toggleable boolean option (equivalent to
+    #     +{boolean: true}+)
+    #   Hash::
+    #     Possible option flags:
+    #     - +:short+: specify a short option letter to associate with the long
+    #       option
+    #     - +:nargs+: specify an exact number or range of possible numbers of
+    #       arguments to the option
+    #     - +:boolean+: if true, specify that the option is a toggleable
+    #       boolean option and allow a prefix of "no" to turn it off.
+    # @param flags [Hash]
+    #   Optional flags dictating how {.parse} should do its job.
+    # @option flags [Boolean] :posix_order
+    #   Stop processing parameters when a non-option argument is seen.
+    #   Set this to +true+ if you want to implement subcommands.
+    #
+    # @return [Array]
+    #   Two-element array containing +opts+ and +args+ return values.
+    #   +opts+::
+    #     The returned +opts+ value will be a Hash with the observed
+    #     options as keys and any option arguments as values.
+    #   +args+::
+    #     The returned +args+ will be an Array of the unprocessed
+    #     parameters (if +:posix_order+ was passed in +flags+, this array might
+    #     contain further options that were not processed after observing a
+    #     non-option parameters).
+    def parse(params, options, flags = {})
+      options = _massage_options(options)
+      opts = {}
+      args = []
+      i = 0
+      while i < params.length
+        param = params[i]
+        if param =~ /^--([^=]+)(?:=(.+))?$/
+          param_name, val = $1, $2
+          bool_val = true
+          if options[param_name].nil?
+            if param_name =~ /^no(.*)$/
+              test_param_name = $1
+              if options[test_param_name]
+                param_name = test_param_name
+                bool_val = false
+              end
             end
           end
-        end
-        opt_config = options[param_name]
-        raise ArgumentParsingException.new("Unknown option '#{param_name}'") unless opt_config
-        param_key = opt_config[:key]
-        if opt_config[:boolean]
-          opts[param_key] = bool_val
-        elsif opt_config[:nargs].last == 0
-          opts[param_key] = true
-        else
-          opts[param_key] = []
-          i += _gather(opt_config[:nargs], i + 1, params, val, param_key, opts[param_key])
-        end
-      elsif param =~ /^-(.+)$/
-        short_flags = $1
-        short_idx = 0
-        while short_idx < short_flags.length
-          opt_config = _find_opt_config_by_short_name(options, short_flags[short_idx])
-          if opt_config.nil?
-            raise ArgumentParsingException.new("Unknown option '-#{short_flags[short_idx]}'")
-          end
+          opt_config = options[param_name]
+          raise ArgumentParsingException.new("Unknown option '#{param_name}'") unless opt_config
           param_key = opt_config[:key]
-          if opt_config[:nargs].last == 0
+          if opt_config[:boolean]
+            opts[param_key] = bool_val
+          elsif opt_config[:nargs].last == 0
             opts[param_key] = true
           else
             opts[param_key] = []
-            i += _gather(opt_config[:nargs], i + 1, params, short_flags[short_idx + 1, short_flags.length], param_key, opts[param_key])
-            break
+            i += _gather(opt_config[:nargs], i + 1, params, val, param_key, opts[param_key])
           end
-          short_idx += 1
+        elsif param =~ /^-(.+)$/
+          short_flags = $1
+          short_idx = 0
+          while short_idx < short_flags.length
+            opt_config = _find_opt_config_by_short_name(options, short_flags[short_idx])
+            if opt_config.nil?
+              raise ArgumentParsingException.new("Unknown option '-#{short_flags[short_idx]}'")
+            end
+            param_key = opt_config[:key]
+            if opt_config[:nargs].last == 0
+              opts[param_key] = true
+            else
+              opts[param_key] = []
+              i += _gather(opt_config[:nargs],
+                           i + 1,
+                           params,
+                           short_flags[short_idx + 1, short_flags.length],
+                           param_key,
+                           opts[param_key])
+              break
+            end
+            short_idx += 1
+          end
+        elsif flags[:posix_order]
+          args = params[i, params.length]
+          break
+        else
+          args << params[i]
         end
-      elsif flags[:posix_order]
-        args = params[i, params.length]
-        break
-      else
-        args << params[i]
+        i += 1
       end
-      i += 1
+
+      # Condense 1-element arrays of option values to just the element itself
+      opts.each_key do |k|
+        if opts[k].is_a?(Array) and opts[k].length == 1
+          opts[k] = opts[k].first
+        end
+      end
+
+      return [opts, args]
     end
 
-    # Condense 1-element arrays of option values to just the element itself
-    opts.each_key do |k|
-      if opts[k].is_a?(Array) and opts[k].length == 1
-        opts[k] = opts[k].first
+    private
+
+    # Internal helper method to gather arguments for an option
+    def _gather(nargs, start_idx, params, initial, param_key, result)
+      n_gathered = 0
+      if initial and initial != ''
+        result << initial
+        n_gathered += 1
+      end
+      num_indices_used = 0
+      index = start_idx
+      while n_gathered < nargs.last and
+            index < params.length and
+            params[index][0] != '-' do
+        result << params[index]
+        index += 1
+        num_indices_used += 1
+        n_gathered += 1
+      end
+      if n_gathered < nargs.first
+        raise ArgumentParsingException.new("Not enough arguments supplied for option '#{param_key}'")
+      end
+      num_indices_used
+    end
+
+    # Internal helper method to format the options in a consistent format
+    def _massage_options(options)
+      {}.tap do |newopts|
+        options.each_pair do |k, v|
+          v = {} if v.nil?
+          v = {boolean: true} if v == :boolean
+          newkey = k.to_s
+          newopts[newkey] = {key: k}
+          nargs = v[:nargs] || 0
+          nargs = (nargs..nargs) if nargs.is_a?(Fixnum)
+          newopts[newkey][:nargs] = nargs
+          newopts[newkey][:short] = v[:short] || ''
+          newopts[newkey][:boolean] = v[:boolean]
+        end
       end
     end
 
-    return [opts, args]
-  end
-
-  # Internal helper method to gather arguments for an option
-  def self._gather(nargs, start_idx, params, initial, param_key, result)
-    n_gathered = 0
-    if initial and initial != ''
-      result << initial
-      n_gathered += 1
-    end
-    num_indices_used = 0
-    index = start_idx
-    while n_gathered < nargs.last and
-          index < params.length and
-          params[index][0] != '-' do
-      result << params[index]
-      index += 1
-      num_indices_used += 1
-      n_gathered += 1
-    end
-    if n_gathered < nargs.first
-      raise ArgumentParsingException.new("Not enough arguments supplied for option '#{param_key}'")
-    end
-    num_indices_used
-  end
-  private_class_method :_gather
-
-  # Internal helper method to format the options in a consistent format
-  def self._massage_options(options)
-    {}.tap do |newopts|
+    # Internal helper method to find an option configuration by short name
+    def _find_opt_config_by_short_name(options, short_name)
       options.each_pair do |k, v|
-        v = {} if v.nil?
-        v = {boolean: true} if v == :boolean
-        newkey = k.to_s
-        newopts[newkey] = {key: k}
-        nargs = v[:nargs] || 0
-        nargs = (nargs..nargs) if nargs.is_a?(Fixnum)
-        newopts[newkey][:nargs] = nargs
-        newopts[newkey][:short] = v[:short] || ''
-        newopts[newkey][:boolean] = v[:boolean]
+        return v if v[:short] == short_name
       end
+      nil
     end
-  end
-  private_class_method :_massage_options
 
-  # Internal helper method to find an option configuration by short name
-  def self._find_opt_config_by_short_name(options, short_name)
-    options.each_pair do |k, v|
-      return v if v[:short] == short_name
-    end
-    nil
   end
-  private_class_method :_find_opt_config_by_short_name
+
 end