Don’t render 404 yourself, there’s no reason to; Rails has this functionality built in already. If you want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this: def not_found raise ActionController::RoutingError.new(‘Not Found’) end Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way. This does two … Read more
On Ubuntu/Debian and other distributions using aptitude: sudo apt-get install libmysql-ruby libmysqlclient-dev Package libmysql-ruby has been phased out and replaced by ruby-mysql. This is where I found the solution. If the above command doesn’t work because libmysql-ruby cannot be found, the following should be sufficient: sudo apt-get install libmysqlclient-dev On Red Hat/CentOS and other distributions … Read more
It’s easy; just do the following: rvm implode or rm -rf ~/.rvm And don’t forget to remove the script calls in the following files: ~/.bashrc ~/.bash_profile ~/.profile And maybe others depending on whatever shell you’re using.
Update for 2022 from TrinitronX Fast-forward to 2021 and now Bundler docs [web archive] now say to commit the Gemfile.lock inside a gem… ¯_(ツ)_/¯ I guess it makes sense for developers and ease of use when starting on a project. However, now CI jobs need to be sure to remove any stray Gemfile.lock files to … Read more
It’s shorthand for tags.map(&:name.to_proc).join(‘ ‘) If foo is an object with a to_proc method, then you can pass it to a method as &foo, which will call foo.to_proc and use that as the method’s block. The Symbol#to_proc method was originally added by ActiveSupport but has been integrated into Ruby 1.8.7. This is its implementation: class … Read more
You may use the different accessors to communicate your intent to someone reading your code, and make it easier to write classes which will work correctly no matter how their public API is called. class Person attr_accessor :age … end Here, I can see that I may both read and write the age. class Person … Read more
You’ve got a workable idea, but the #flatten! is in the wrong place — it flattens its receiver, so you could use it to turn [1, 2, [‘foo’, ‘bar’]] into [1,2,’foo’,’bar’]. I’m doubtless forgetting some approaches, but you can concatenate: a1.concat a2 a1 + a2 # creates a new array, as does a1 += a2 … Read more
kind_of? and is_a? are synonymous. instance_of? is different from the other two in that it only returns true if the object is an instance of that exact class, not a subclass. Example: “hello”.is_a? Object and “hello”.kind_of? Object return true because “hello” is a String and String is a subclass of Object. However “hello”.instance_of? Object returns … Read more
I’m going to heavily quote the Object documentation here, because I think it has some great explanations. I encourage you to read it, and also the documentation for these methods as they’re overridden in other classes, like String. Side note: if you want to try these out for yourself on different objects, use something like … Read more
Use the defined? keyword (documentation). It will return a String with the kind of the item, or nil if it doesn’t exist. >> a = 1 => 1 >> defined? a => “local-variable” >> defined? b => nil >> defined? nil => “nil” >> defined? String => “constant” >> defined? 1 => “expression” As skalee … Read more