Download

Type ‘gem install method_args’ or download manually at rubyforge.org/projects/method-args

Synopses

This extension adds args method to the Method class. Example:

require 'method_args'
class X
  def hello(foo, bar)
    nil
  end
end
x = X.new
m = x.method(:hello)
m.args  # => [:foo, :bar]

To differentiate between the different types of arguments that could be returned the library provides

Method#required_args
Method#optional_args
Method#splat_arg

For example:

class X
  def hello(i, love = 2, *techno)
  end
end
method = X.new.method(:hello)
method.required_args # => [:i]
method.optional_args # => [:love]
method.splat_arg # => :techno

Method#args does not support methods written in C (and never will). To test if you can call args methods on a certain method use Method#args?. Example:

X.new.args? # => true
built_in = "string".method(:split)
built_in.args? # => false
built_in.args  # => raises StandardError

Method#args does not support block arguments (but might in the future).

Acknowledgments

Most of the code here is extracted from ParseTree by Ryan Davis

License

(The MIT License)

Copyright © 2007 Ryan Dahl <ry@tinyclouds.org>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sub-license, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.