ruby metaprogramming - getting method names and parameter info for a class

Question

I want to get class methods in an object. Please see the following example I have a class "user.rb"

class User
  def say_name

  end

  def walk(p1)

  end

  def run(p1, p2)

  end
end

and I wrote the following code

require 'user.rb'

a = User.new

arr = a.public_methods(all = false)

Above code will return the method name, But my question is I want to get the method name with parameters

def def run(p1, p2)

end

I want to get the method name ("run") and its parameter names (p1, p2) or parameter count (2)

can someone help me, thanks in advance

cheers

sameera

Gishu · Accepted Answer · 2010-10-08 09:15:43Z

5

User.new.method(:run).arity   # => 2

answered Oct 8, 2010 at 9:15

Gishu

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1 Comment

or, if you dont want to create an instance: User.instance_method(:run).arity #=> 2

rogerdpack · Accepted Answer · 2010-10-09 20:11:56Z

1

if you want parameters then http://github.com/rdp/arguments is your friend

answered Oct 9, 2010 at 20:11

rogerdpack

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Tim Scott · Accepted Answer · 2017-08-24 18:50:14Z

1

You want:

User.new.method(:run).parameters # => [[:req, :p1], [:req, :p2]]

req means it's a required field. Other values you might get are:

answered Aug 24, 2017 at 18:50

Tim Scott

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