From: Dave Thomas <Dave@...>
Date: 2001-02-25T15:46:46+09:00
Subject: [ruby-talk:11511] ANN: ri - the Ruby Interactive reference


Have you forgotten the parameters that each_with index passes to it's
block? Just type:

   % ri each_with_index

and you'll see:

   ------------------------------------------------------------------
     enumObj.each_with_index {| obj, i | block }  -> nil
   ------------------------------------------------------------------
     Calls block with two arguments, the item and its index, for each
     item in enumObj.

        hash = Hash.new
        %w(cat dog wombat).each_with_index {|item, index|
          hash[item] = index
        }
        hash   #=> {"dog"=>1, "wombat"=>2, "cat"=>0}


Hazy on what methods are defined in the Math module?

   % ri Math
   -------------------------------------------------------------------
     module: Math  
   -------------------------------------------------------------------
     The Math module contains module functions for basic trigonometric
     and transcendental functions.
   -------------------------------------------------------------------
     atan2, cos, exp, frexp, ldexp, log, log10, sin, sqrt, tan
   -------------------------------------------------------------------

ri contains the information from Programming Ruby on 42 built-in
classes and modules, and over 700 built-in methods. What command line
could be complete without a copy of ri?

Snag one while they last at:

   http://www.pragmaticprogrammer.com/ruby/downloads/ri.html


Dave


ps.

If anyone writes editor macros that use ri, so that you can pop-up
method descriptions while your cursor is on the method name, I'd love
to add them to the distribution. Thanks.