diff --git a/src/argparse.lua b/src/argparse.lua
index c2fece2..d93bcf3 100644
--- a/src/argparse.lua
+++ b/src/argparse.lua
@@ -2,34 +2,25 @@ local argparse = {}
 
 local class = require "30log"
 
-local State = require "argparse.state"
-local utils = require "argparse.utils"
+local State = class {
+   context = {}, -- {alias -> element}
+   result = {}
+}
 
-local Parser = class()
-
-function Parser:__init(options)
-   options = options or {}
-   self.description = options.description
-   self.name = options.name
-   self.no_help = options.no_help
-   self.must_command = options.must_command
-
-   self.arguments = {}
-   self.elements = {}
-   self.groups = {}
-   self.commands = {}
-   self.context = {}
+function State:__init(parser)
+   self:switch(parser)
 end
 
-function Parser:add_alias(element, alias)
-   table.insert(element.aliases, alias)
-   self.context[alias] = element
-end
+function State:switch(parser)
+   self.parser = parser
+   self.parser:make_targets()
 
-function Parser:apply_options(element, options)
-   for k, v in pairs(options) do
-      element[k] = v -- fixme
+   for _, option in ipairs(parser.options) do
+      table.insert(self.options, option)
    end
+
+   self.arguments = parser.arguments
+   self.commands = parser.commands
 end
 
 function Parser:make_target(element)
@@ -45,151 +36,297 @@ function Parser:make_target(element)
    end
 end
 
--- TODO: make it declarative as it was
-function Parser:argument(name, ...)
-   local element = {
-      name = name,
-      aliases = {},
-      count = 1,
-      args = 1,
-      type = "argument"
-   }
 
-   self:add_alias(element, name)
 
-   local argument
-   for i = 1, select('#', ...) do
-      argument = select(i, ...)
+function State:parse(args)
+   args = args or arg
 
-      if type(argument) == "string" then
-         self:add_alias(element, argument)
+
+
+function State:handle_option(name)
+   local option = self:_assert(self.context[name], "unknown option %s", name)
+
+   self:_open(option)
+end
+
+function State:handle_argument(data)
+   if self._current then
+      if self:_can_pass(self._current) then
+         self:_pass(self._current, data)
+         return
       else
-         self:apply_options(element, argument)
+         self._current = nil
       end
    end
 
-   self:make_target(element)
-
-   element.mincount, element.maxcount = utils.parse_boundaries(element.count)
-   element.minargs, element.maxargs = utils.parse_boundaries(element.args)
-
-   table.insert(self.arguments, element)
-   table.insert(self.elements, element)
-
-   return element
+   local argument = self._arguments[self._next_arg_i]
+   if argument then
+      self:_open(argument)
+      self:_pass(argument, data)
+   else
+      local command = self.context[data]
+      if command and command.type == "command" then
+         self._result[command.target] = {{}}
+         self:_switch(command)
+      else
+         if #self._commands > 0 then
+            self:_error("unknown command %s", data)
+         else
+            self:_error("too many arguments")
+         end
+      end
+   end
 end
 
-function Parser:option(name, ...)
-   local element = {
-      name = name,
-      aliases = {},
-      count = "0-1",
-      args = 1,
-      type = "option"
-   }
+function State:get_result()
+   self:_check()
 
-   self:add_alias(element, name)
+   local result = {}
 
-   local argument
-   for i = 1, select('#', ...) do
-      argument = select(i, ...)
+   local invocations
+   for _, element in ipairs(self._all_elements) do
+      invocations = self._result[element.target]
 
-      if type(argument) == "string" then
-         self:add_alias(element, argument)
+      if element.maxcount == 1 then
+         if element.maxargs == 0 then
+            if #invocations > 0 then
+               result[element.target] = true
+            end
+         elseif element.maxargs == 1 and element.minargs == 1 then
+            if #invocations > 0 then
+               result[element.target] = invocations[1][1]
+            end
+         else
+            result[element.target] = invocations[1]
+         end
       else
-         self:apply_options(element, argument)
+         if element.maxargs == 0 then
+            result[element.target] = #invocations
+         elseif element.maxargs == 1 and element.minargs == 1 then
+            local new_result = {}
+            for i, passed in ipairs(invocations) do
+               new_result[i] = passed[1]
+            end
+            result[element.target] = new_result
+         else
+            result[element.target] = invocations
+         end
       end
    end
 
-   self:make_target(element)
-
-   element.mincount, element.maxcount = utils.parse_boundaries(element.count)
-   element.minargs, element.maxargs = utils.parse_boundaries(element.args)
-
-   table.insert(self.elements, element)
-
-   return element
+   return result
 end
 
--- DRY?
+function State:_check()
+   self:_assert(not self._parser.must_command, "a command is required")
 
-function Parser:flag(name, ...)
-   local element = {
-      name = name,
-      aliases = {},
-      count = "0-1",
-      args = 0,
-      type = "option"
-   }
+   local invocations
+   for _, element in ipairs(self._all_elements) do
+      invocations = self._result[element.target] or {}
 
-   self:add_alias(element, name)
+      if element.type == "argument" and #invocations == 0 then
+         invocations[1] = {}
+      end
 
-   local argument
-   for i = 1, select('#', ...) do
-      argument = select(i, ...)
+      if #invocations > element.maxcount then
+         if element.no_overwrite then
+            self:_error("option %s must be used at most %d times", element.name, element.maxcount)
+         else
+            local new_invocations = {}
+            for i = 1, element.maxcount do
+               new_invocations[i] = invocations[#invocations-element.maxcount+i]
+            end
+            invocations = new_invocations
+         end
+      end
 
-      if type(argument) == "string" then
-         self:add_alias(element, argument)
-      else
-         self:apply_options(element, argument)
+      self:_assert(#invocations >= element.mincount, "option %s must be used at least %d times", element.name, element.mincount)
+
+      for _, passed in ipairs(invocations) do
+         self:_assert(#passed <= element.maxargs, "too many arguments")
+         if #passed < element.minargs then
+            if element.default then
+               for i = 1, element.minargs-#passed do
+                  table.insert(passed, element.default)
+               end 
+            else
+               self:_error("too few arguments")
+            end
+         end
+      end
+
+      self._result[element.target] = invocations
+   end
+
+   for _, group in ipairs(self._all_groups) do
+      local invoked
+      for _, element in ipairs(group.elements) do
+         if #self._result[element.target] > 0 then
+            if invoked then
+               self:_error("%s can not be used together with %s", invoked.name, element.name)
+            else
+               invoked = element
+            end
+         end
+      end
+
+      if group.required then
+         self:_assert(invoked, "WIP(required mutually exclusive group)")
+      end
+   end
+end
+
+function State:_open(element)
+   if not self._result[element.target] then
+      self._result[element.target] = {}
+   end
+
+   table.insert(self._result[element.target], {})
+
+   if element.type == "argument" then
+      self._next_arg_i = self._next_arg_i+1
+   end
+
+   self._current = element
+end
+
+function State:_can_pass(element)
+   local invocations = self._result[element.target]
+   local passed = invocations[#invocations]
+
+   return #passed < element.maxargs
+end
+
+function State:_pass(element, data)
+   local invocations = self._result[element.target]
+   local passed = invocations[#invocations]
+
+   table.insert(passed, data)
+end
+
+function State:_switch(command)
+   self._parser = command
+   self._arguments = command.arguments
+   self._commands = command.commands
+
+   for _, element in ipairs(command.elements) do
+      table.insert(self._all_elements, element)
+   end
+
+   for _, group in ipairs(command.groups) do
+      table.insert(self._all_groups, group)
+   end
+
+   self.context = setmetatable(command.context, {__index = self.context})
+   self._next_arg_i = 1
+end
+
+function State:_error(...)
+   return self._parser:error(...)
+end
+
+function State:_assert(...)
+   return self._parser:assert(...)
+end
+
+
+local utils = require "argparse.utils"
+
+local Declarative = {}
+
+function Declarative:__init(...)
+   return self(...)
+end
+
+function Declarative:__call(...)
+   local name_or_options
+
+   for i=1, select("#", ...) do
+      name_or_options = select(i, ...)
+
+      if type(name_or_options) == "string" then
+         self:set_name(name_or_options)
+      elseif type(name_or_options) == "table" then
+         for _, field in ipairs(self.fields) do
+            if name_or_options[field] ~= nil then
+               self[field] = name_or_options[field]
+            end
+         end
       end
    end
 
-   self:make_target(element)
-
-   element.mincount, element.maxcount = utils.parse_boundaries(element.count)
-   element.minargs, element.maxargs = utils.parse_boundaries(element.args)
-
-   table.insert(self.elements, element)
-
-   return element
+   return self
 end
 
-function Parser:command(name, ...)
-   local element = {
-      name = name,
-      aliases = {},
-      count = "0-1",
-      args = 0,
-      type = "command"
-   }
+local Aliased = {}
 
-   local command = Parser() -- fixme
-   for k, v in pairs(element) do
-      command[k] = v
+function Aliased:set_name(name)
+   table.insert(self.aliases, name)
+
+   if not self.name then
+      self.name = name
    end
+end
 
-   self:add_alias(command, name)
+local Named = {}
 
-   local argument
-   for i = 1, select('#', ...) do
-      argument = select(i, ...)
-      self:add_alias(command, argument)
-   end
+function Named:set_name(name)
+   self.name = name
+end
 
-   self:make_target(command)
+local Parser = class {
+   arguments = {},
+   options = {},
+   commands = {},
+   charset = {"-"},
+   fields = {"name", "description", "target"}
+}:include(Declarative):include(Named)
 
-   command.mincount, command.maxcount = utils.parse_boundaries(command.count)
-   command.minargs, command.maxargs = utils.parse_boundaries(command.args)
+local Command = Parser:extends {
+   aliases = {}
+}:include(Declarative):include(Aliased)
 
-   table.insert(self.elements, command)
+local Argument = class {
+   args = 1,
+   count = 1,
+   fields = {"name", "description", "target", "args", "default", "convert"}
+}:include(Declarative):include(Named)
 
+local Option = class {
+   aliases = {},
+   args = 1,
+   count = "?",
+   fields = {"name", "aliases", "description", "target", "args", "count", "default", "convert"}
+}:include(Declarative):include(Aliased)
+
+local Flag = Option:extends {
+   args = 0
+}:include(Declarative):include(Aliased)
+
+function Parser:argument(...)
+   local argument = Argument(...)
+   table.insert(self.arguments, argument)
+   return argument
+end
+
+function Parser:option(...)
+   local option = Option(...)
+   table.insert(self.options, option)
+   return option
+end
+
+function Parser:flag(...)
+   local flag = Flag(...)
+   table.insert(self.options, flag)
+   return flag
+end
+
+function Parser:command(...)
+   local command = Command(...)
+   table.insert(self.commands, command)
    return command
 end
 
-function Parser:group(...)
-   --
-end
-
-function Parser:mutually_exclusive(...)
-   local group = {
-      elements = {...}
-   }
-
-   table.insert(self.groups, group)
-   return group
-end
-
 function Parser:error(fmt, ...)
    local msg = fmt:format(...)
    io.stderr:write("Error: " .. msg .. "\n")
@@ -200,6 +337,51 @@ function Parser:assert(assertion, ...)
    return assertion or self:error(...)
 end
 
+function Parser:get_charset()
+   for _, command in ipairs(self.commands) do
+      for char in command:get_charset() do
+         self.charset[char] = true
+      end
+   end
+
+   for _, option in ipairs(self.options) do
+      for _, alias in ipairs(option.aliases) do
+         self.charset[alias:sub(1, 1)] = true
+      end
+   end
+
+   return self.charset
+end
+
+-- to be called from State
+function Parser:make_targets()
+   for _, option in ipairs(self.options) do
+      if not option.target then
+         for _, alias in ipairs(option.aliases) do
+            if alias:sub(1, 1) == alias:sub(2, 2) then
+               option.target = alias:sub(3)
+               break
+            end
+         end
+      end
+
+      option.target = option.target or option.aliases[1]:sub(2)
+   end
+
+   for _, argument in ipairs(self.arguments) do
+      argument.target = argument.target or argument.name
+   end
+
+   for _, command in ipairs(self.commands) do
+      command.target = command.target or command.name
+   end
+end
+
+function Parser:parse(args)
+   self:get_charset()
+   return State(self):parse(args)
+end
+
 
 function Parser:parse(args)
    args = args or arg
diff --git a/src/interface.lua b/src/interface.lua
new file mode 100644
index 0000000..98322f0
--- /dev/null
+++ b/src/interface.lua
@@ -0,0 +1,101 @@
+-- new, awesome declarative interface implementation
+
+local class = require "30log"
+
+local Declarative = class()
+
+function Declarative:__init(...)
+   return self(...)
+end
+
+function Declarative:__call(...)
+   local name_or_options
+
+   for i=1, select("#", ...) do
+      name_or_options = select(i, ...)
+
+      if type(name_or_options) == "string" then
+         self:set_name(name_or_options)
+      elseif type(name_or_options) == "table" then
+         for _, field in ipairs(self.fields) do
+            if name_or_options[field] ~= nil then
+               self[field] = name_or_options[field]
+            end
+         end
+      end
+   end
+
+   return self
+end
+
+local Aliased = {}
+
+function Aliased:set_name(name)
+   table.insert(self.aliases, name)
+
+   if not self.name then
+      self.name = name
+   end
+end
+
+local Named = {}
+
+function Named:set_name(name)
+   self.name = name
+end
+
+local Parser = class {
+   arguments = {},
+   options = {},
+   commands = {},
+   groups = {},
+   mutex_groups = {},
+   fields = {"name", "description", "target"}
+}:include(Declarative):include(Named)
+
+local Command = Parser:extends {
+   aliases = {}
+}:include(Declarative):include(Aliased)
+
+local Argument = class {
+   args = 1,
+   count = 1,
+   fields = {"name", "description", "target", "args", "default", "convert"}
+}:include(Declarative):include(Named)
+
+local Option = class {
+   aliases = {},
+   args = 1,
+   count = "?",
+   fields = {"name", "aliases", "description", "target", "args", "count", "default", "convert"}
+}:include(Declarative):include(Aliased)
+
+local Flag = Option:extends {
+   args = 0
+}:include(Declarative):include(Aliased)
+
+function Parser:argument(...)
+   local argument = Argument(...)
+   table.insert(self.arguments, argument)
+   return argument
+end
+
+function Parser:option(...)
+   local option = Option(...)
+   table.insert(self.options, option)
+   return option
+end
+
+function Parser:flag(...)
+   local flag = Flag(...)
+   table.insert(self.options, flag)
+   return flag
+end
+
+function Parser:command(...)
+   local command = Command(...)
+   table.insert(self.commands, command)
+   return command
+end
+
+return Parser
diff --git a/src/interface_test.lua b/src/interface_test.lua
new file mode 100644
index 0000000..b56dd29
--- /dev/null
+++ b/src/interface_test.lua
@@ -0,0 +1,39 @@
+--Just some testing
+
+local MetaParser = require "interface"
+
+local parser = MetaParser "luarocks" {
+   description = "a module deployment system for Lua"
+}
+
+parser:option "--server" "-s" {
+   description = "Fetch rocks/rockspecs from this server"
+}
+
+parser:flag "--local" "-l" {
+   description = "Use the tree in the user's home directory."
+}
+
+local install = parser:command "install" "i"
+
+install:argument "rock"
+
+install:argument "version" {
+   args = "?"
+}
+
+assert(parser.description == "a module deployment system for Lua")
+assert(parser.options[1].name == "--server")
+assert(parser.options[1].aliases[1] == "--server")
+assert(parser.options[1].aliases[2] == "-s")
+assert(parser.options[1].description == "Fetch rocks/rockspecs from this server")
+assert(parser.options[1].args == 1)
+assert(parser.options[1].count == "?")
+assert(parser.options[2].name == "--local")
+assert(parser.options[2].args == 0)
+assert(parser.commands[1] == install)
+assert(install.arguments[1].name == "rock")
+assert(install.aliases[2] == "i")
+assert(install.arguments[2].name == "version")
+assert(install.arguments[2].count == 1)
+assert(install.arguments[2].args == "?")
diff --git a/src/state.lua b/src/state.lua
index 7f52470..4f0f9ff 100644
--- a/src/state.lua
+++ b/src/state.lua
@@ -1,6 +1,8 @@
 local class = require "30log"
 
-local State = class()
+local State = class {
+   context = {}
+}
 
 function State:__init(parser)
    self.context = {}