Ruby operator precedence table

Show me a definitive, peer-reviewed/maintained Ruby precedence table (of operators, non-operators, and modifiers). Over the years I have had to rely on the following sources for this information: 1. – The Pickaxe book, which documents Ruby 1.6, which was released in September 2000, and includes a formatting error or typo ({ is listed as […]

What is the colon operator in Ruby?

When I say { :bla => 1, :bloop => 2 }, what exactly does the : do? I read somewhere about how it’s similar to a string, but somehow a symbol. I’m not super-clear on the concept, could someone enlighten me?

How to use ckan gem Comprehensive Knowledge Archive Network

Does anyone have a link to a tutorial on how to use the Ruby ‘ckan‘ gem (Comprehensive Knowledge Archive Network). I want to access data , I downloaded the gem but how do I get to the data ? The documentation seems a bit sparse in this area Many thanks for any help. My […]

How to dynamically create a local variable?

I have a variable var = “some_name” and I would like to create a new object and assign it to some_name. How can I do it? E.g. var = “some_name” some_name = # I need this a =‘blah’) # so that I can do this.

How can I get source code of a method dynamically and also which file is this method locate in

I would like to know whether I can get source code a method on the fly, and whether I can get which file is this method in. like

Error to install Nokogiri on OSX 10.9 Maverick?

I upgraded my OSX (Lion) to Mavericks and I can’t install Nokogiri for my projects. I already install XCode 5.0.1, Command Line Tools (using xcode-select –install), and already installed libxml2 from Homebrew and I am still having problems. The error is: Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension. /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/bin/ruby extconf.rb checking for libxml/parser.h… *** […]

Ruby's double colon (::) operator usage differences

Is there any difference between module Foo class Engine < Rails::Engine end end and module Foo class Engine < ::Rails::Engine end end

Gem – require filename and path

With any given gem is there a way to determine what you need to require to use the gem? e.g. I had a look at this issue on github and it’s clearly not obvious in this case what file needed to be used in the require.

How to make rails code reloaded each request

I’d like to play with rails code to understand it deeper and how everything works internally. And it could be very nice to change rails code and see the changes after reloading page (by default I need to restart server), what is the right way?

Using Jbuilder, Not able to get Json output instead of that showing error like undefined method `dump' for MultiJson:Module

Please find here is my controller and json file //controller file module Api module V1 class CouponsController < ApplicationController respond_to :json def show @coupon = Coupon.find(params[:id]) render “/coupons/show.json.jbuilder” end end end end //show.json.jbuilder json.extract! @coupon, :id, :category

Ruby is the best programming language in the world - Ruby on Rails.