options instead of arguments. arguments checking against arity if lambda. help improved.

lib/dencli/cmd.rb

@@ -1,33 +1,62 @@
 require_relative '../dencli'
 
 class DenCli::CMD
-	attr_reader :parent, :name, :description, :exe, :completion, :arguments
+	attr_reader :parent, :name, :description, :exe, :completion, :options
 
 	def initialize parent, name, description, exe
 		raise "Proc expected, instead of: #{exe.inspect}"  unless Proc === exe
-		@parent, @name, @description, @exe = parent, name, description, exe
+		@parent, @name, @description, @exe = parent, name, description, lambda( &exe)
-		@arguments = []
+		@options = []
 		completion {|*a| [] }
 	end
 
 	def _full_cmd( post) parent._full_cmd [@name]+post end
 	def full_cmd() _full_cmd [] end
+
+	def parameters() @exe.parameters end
+	def required() @exe.parameters.select{|e|:req == e[0]}.map{|e|e[1]} end
+	def additional() @exe.parameters.select{|e|:opt == e[0]}.map{|e|e[1]} end
+
 	def call( *as)
-		if @arguments.empty?
+		if @options.empty?
 			@exe.call *as
 		else
 			os = {}
 			options = OptionParser.new
 			options.banner = "#{full_cmd.join ' '}"
-			@arguments.each do |(aname, aas, aos, aexe)|
+			@options.each do |(aname, aas, aos, aexe)|
 				os[aname] = aos[aname]  if aos.has_key? :default
 				options.on( *aas) {|val| os[aname] = aexe[val] }
 			end
 			as = options.parse! as
+			if @exe.lambda?
+				pars = required
+				if as.length < pars.length
+					raise DenCli::UsageError, "Missing parameter(s): #{pars[as.length..-1].join " "}"
+				end
+				if parameters.select{|e|:rest == e[0]}.empty?
+					pars = pars + additional
+					if as.length > pars.length
+						raise DenCli::UsageError, "Unused parameter(s): #{as[-pars.length..-1].shelljoin}"
+					end
+				end
+			end
 			@exe.call *as, **os
 		end
 	end
-	def help() "#{parent.full_cmd.join ' '} #{name}\n#{description}" end
+
+	def usage
+		"#{parent.full_cmd.join ' '} #{name} "+
+			@options.map{|(_,(o,_,_,_),_)|"[#{o}] "}.join( '')+
+			(@exe.lambda? ? (
+				required.join( " ")+
+				(additional.empty? ? "" : " [#{additional.join " "}]")
+			) : '...')
+	end
+
+	def help
+		"#{usage}\n#{description}"
+	end
 
 	def complete( *pre, str) @completion.call *pre, str end
 
@@ -36,8 +65,8 @@ class DenCli::CMD
 		self
 	end
 
-	def arg name, *as, **os, &exe
+	def opt name, *as, **os, &exe
-		@arguments.push [name.to_s.to_sym, as, os, exe || lambda{|*a|a} ]
+		@options.push [name.to_s.to_sym, as, os, exe || lambda{|val|val} ]
 		self
 	end
 

lib/dencli/sub.rb

@@ -11,12 +11,16 @@ class DenCli::Sub
 	def full_cmd() _full_cmd [] end
 	def []( k) @aliases[k] end
 
+	def usage
+		"#{full_cmd.join ' '} ..."
+	end
+
 	def help n = nil, *a
 		if n.nil?
 			r = "#{full_cmd.join ' '}: #{description}\n\n"
-			m = @subs.map {|k,_| k.length }.max
+			m = @subs.map {|k,c| k.nil? ? 0 : c.usage.length }.max
 			@subs.each do |k, c|
-				r += "  % -#{m}s  %s\n" % [k, c.description]  unless k.nil?
+				r += "  % -#{m}s  %s\n" % [c.usage, c.description]  unless k.nil?
 			end
 			r
 		elsif @aliases.has_key? n