From *[How To – Persist Rails or IRB Console Command History After Exit][1]*.

Create, or edit your `~/.irbrc` file to include:

    require &#39;irb/ext/save-history&#39;
    IRB.conf[:SAVE_HISTORY] = 200
    IRB.conf[:HISTORY_FILE] = &quot;#{ENV[&#39;HOME&#39;]}/.irb-history&quot;

  [1]: http://www.wetware.co.nz/2010/09/how-to-persist-rails-or-irb-console-command-history-after-exit/


Currently i have a xsl with following code where I&#39;m trying print out &quot;count&quot; only if it is not equal to `N/A`. but seems like `&quot;!=&quot;` is not working. 

    &lt;xsl:for-each select=&quot;Directory/Match&quot;&gt;
        &lt;xsl:if test = &quot;Count != N/A&quot;&gt;
            &lt;tr&gt;
                &lt;td&gt;&lt;xsl:value-of select=&quot;@bookName&quot; /&gt;&lt;/td&gt;
                &lt;td&gt;&lt;xsl:value-of select=&quot;@AuthorName&quot; /&gt;&lt;/td&gt;
                &lt;td&gt;&lt;xsl:value-of select=&quot;Count&quot; /&gt;&lt;/td&gt;
            &lt;/tr&gt;
        &lt;/xsl:if&gt;
    &lt;/xsl:for-each&gt;

However, it works if I try to compare it with numeric value.

Example:

    &lt;xsl:if test = &quot;Occurrances != 0&quot;&gt;

Can someone please tell me: If I would like to compare strings what can I use?


How do I specify &quot;not equals to&quot; when comparing strings in an XSLT &lt;xsl:if&gt;?

How would I render a dynamic definition list using AngularJS?

Example:

Data:

    [
        {
            key: &#39;a&#39;,
            value: &#39;x&#39;
        }, {
            key: &#39;b&#39;,
            value: &#39;y&#39;
        }
    ]

Desired HTML:

    &lt;dl&gt;
        &lt;dt&gt;a&lt;/dt&gt;
        &lt;dd&gt;x&lt;/dd&gt;
        &lt;dt&gt;b&lt;/dt&gt;
        &lt;dd&gt;y&lt;/dd&gt;
    &lt;/dl&gt;

The example at http://docs.angularjs.org/tutorial/step_08:

    &lt;dl&gt;
        &lt;dt&gt;Availability&lt;/dt&gt;
        &lt;dd ng-repeat=&quot;availability in phone.availability&quot;&gt;{{availability}}&lt;/dd&gt;
    &lt;/dl&gt;

works for a dynamic number of dds and a static number of dts, but not a dynamic number of both.

How would I render a dynamic definition list using AngularJS?

I&#39;m using the console in Ruby on Rails 3.1.1, and I&#39;m finding its command history (up arrow) to be really flaky. I&#39;ve run the commands `p = Product.by_name &#39;Acme&#39;` and `p.add_search_term(&#39;Snipe&#39;)` several times today, across several console sessions. 

Yet, when I reload the Ruby on Rails console, only the first one shows in my command history, not the second. Sometimes they are both there in the history after I reload the console. On top of that, I see commands in my history that are from several days ago after pressing up arrow only a few times. Is there some sort of configuration that I need to change or is this a bug? 

 * Ruby on Rails 3.1.1`
 * Ruby 1.9.2p290`
 * Ubuntu 11.10`

Can I get the Ruby on Rails console to remember my command history, umm, better?

<p>I'm using the console in Ruby on Rails 3.1.1, and I'm finding its command history (up arrow) to be really flaky. I've run the commands <code>p = Product.by_name 'Acme'</code> and <code>p.add_search_term('Snipe')</code> several times today, across several console sessions.</p>
<p>Yet, when I reload the Ruby on Rails console, only the first one shows in my command history, not the second. Sometimes they are both there in the history after I reload the console. On top of that, I see commands in my history that are from several days ago after pressing up arrow only a few times. Is there some sort of configuration that I need to change or is this a bug?</p>
<ul>
<li>Ruby on Rails 3.1.1`</li>
<li>Ruby 1.9.2p290`</li>
<li>Ubuntu 11.10`</li>
</ul>


I am using Ruby on Rails 3.2.2 and I would like to &quot;easily&quot; / &quot;quickly&quot; change hash keys from `Symbol`s to `String`s. That is, from `{:one =&gt; &quot;Value 1&quot;, :two =&gt; &quot;Value 2&quot;, ...}` to `{&quot;one&quot; =&gt; &quot;Value 1&quot;, &quot;two&quot; =&gt; &quot;Value 2&quot;, ...}`.

How can I make that by using less code as possible?

How to change hash keys from `Symbol`s to `String`s?

When I run:  

    rails new blog

I get:

    Installing json (1.7.3)
    Gem::InstallError: The &#39;json&#39; native gem requires installed build tools.

    Please update your PATH to include build tools or download the DevKit
    from &#39;http://rubyinstaller.org/downloads&#39; and follow the instructions
    at &#39;http://github.com/oneclick/rubyinstaller/wiki/Development-Kit&#39;
    An error occurred while installing json (1.7.3), and Bundler cannot continue.
    Make sure that `gem install json -v &#39;1.7.3&#39;` succeeds before bundling.

When I run:  

    gem install json -v 1.7.3

I get:

    Please update your PATH to include build tools or download the DevKit
    from &#39;http://rubyinstaller.org/downloads&#39; and follow the instructions
    at &#39;http://github.com/oneclick/rubyinstaller/wiki/Development-Kit&#39;

I&#39;m using Windows 8.  I do have `c:\ruby193\bin` in my path.  What do I do to remedy these errors?

gem install json -v 1.7.3 gives &#39;Please update your PATH to include build tools&#39;

Question: when do I need to use self in my models in Rails?

I have a `set` method in one of my models.

    class SomeData &lt; ActiveRecord::Base
      def set_active_flag(val)
        self.active_flag = val
        self.save!
      end
    end

When I do this, everything works fine. However, when I do this: 

    class SomeData &lt; ActiveRecord::Base
      def set_active_flag(val)
        active_flag = val
        save!
      end
    end

The active_flag value doesn&#39;t change, rather it fails silently. Can someone explain? 

I can&#39;t find any duplicates, but if someone finds one that&#39;s fine too.

When to use self in Model?

I had originally created a table with column as

    t.string   &quot;email&quot;,  :default =&gt; &quot;&quot;, :null =&gt; false

The requirement has changed and now I need to allow email to be null. How can I write a migration to make :null =&gt; true

Rails Migration to make a column null =&gt; true

I&#39;m still new to rails/ruby/bundler and am a little confused.

In our `config/application.rb` file there&#39;s this bundler segment:

    if defined?(Bundler)         
      # If you precompile assets before deploying to production, use this line
      Bundler.require(*Rails.groups(:assets =&gt; %w(development test)))
      # If you want your assets lazily compiled in production, use this line
      # Bundler.require(:default, :assets, Rails.env)
    end

and in our `Gemfile` we use different groups, e.g.                                                                                                                                                                                    

    group :development, :test do
      gem &quot;rspec-rails&quot;, &quot;&gt;= 2.7.0&quot;, :group =&gt; [:development, :test]
      gem &#39;shoulda-matchers&#39;
      gem &#39;watchr&#39;
      gem &#39;spork&#39;, &#39;~&gt; 1.0rc&#39;
      gem &#39;spectator&#39;                          
      gem &#39;debugger&#39;
      gem &#39;wirble&#39;
    end

But when I run `RAILS_ENV=production bundle install` (or `bundle install --deployment`), it still installs gems from the development/test group...

Why does this happens or how can I make this work properly?

Rails bundle install production only

I have this testingdatabase which, by now, is stuffed with junk. Now I&#39;ve done a few Table.destroy_all commands in the rails console which deletes all records and dependencies which is awesome. However; I&#39;d like to truncate everything so the ID&#39;s etc. start at 1 again. Is there any way in Rails 3?

Truncate table(s) with rails console

When I want to try or debug smthing I run `rails console` and do some stuff there. I can print some text or variables from code by raising exception with `raise &quot;blablabla&quot;`.
**Question:** How I can just write to *rails console* without exception raising (and obvious breaking code execution) like a simple `logger.info &quot;blah&quot;`?

Write to rails console

So I have an array of user ids. Is there a way in rails console to query all of these user&#39;s with the array

something like

    ids = [1, 2, 3, 4]
    
    users = User.find(ids)

and have it return all 4 users?

Rails Console find users by array of ids

I`m in root of my application, and when I type

    $ rails console

It looks like something is loading, but nothing happens.

And when I stop `^C` I received this trace:

    ^C/home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client/run.rb:54:in `gets&#39;: Interrupt
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client/run.rb:54:in `verify_server_version&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client/run.rb:25:in `call&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client/command.rb:7:in `call&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client/rails.rb:23:in `call&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client/command.rb:7:in `call&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/client.rb:26:in `run&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/bin/spring:48:in `&lt;top (required)&gt;&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/binstub.rb:11:in `load&#39;
    from /home/jonatas/.rvm/gems/ruby-2.1.2/gems/spring-1.1.3/lib/spring/binstub.rb:11:in `&lt;top (required)&gt;&#39;
    from /home/jonatas/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require&#39;
    from /home/jonatas/.rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require&#39;
    from /home/jonatas/Code/Ruby/jonatasteixeira/bin/spring:16:in `&lt;top (required)&gt;&#39;
    from bin/rails:3:in `load&#39;
    from bin/rails:3:in `&lt;main&gt;&#39;

I have no idea whats going on..



rails console doesn&#39;t start

I have a simple model called PhoneNumber:

    class PhoneNumber &lt; ActiveRecord::Base
      validates :pnumber, presence: true, on: :create #=&gt; { :message =&gt; &quot; cannot be blank&quot; }
      validates :pnumber, numericality: true, on: :create
    end

I go to the root folder of the application (the one containing the app sub-folder) and start the console:

    rails console --sandbox

When I try to create an empty PhoneNumber (I want to get an error message as the validation shall fail) I am getting the following error message:

    2.0.0-p451 :001 &gt; PhoneNumber.new
    NameError: uninitialized constant PhoneNumber
	from (irb):1
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/commands/console.rb:90:in `start&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/commands/console.rb:9:in `start&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/commands/commands_tasks.rb:69:in `console&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/commands/commands_tasks.rb:40:in `run_command!&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/commands.rb:17:in `&lt;top (required)&gt;&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/app_rails_loader.rb:43:in `require&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/app_rails_loader.rb:43:in `block in exec_app_rails&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/app_rails_loader.rb:32:in `loop&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/app_rails_loader.rb:32:in `exec_app_rails&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/lib/rails/cli.rb:5:in `&lt;top (required)&gt;&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/bin/rails:9:in `require&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/gems/railties-4.1.5/bin/rails:9:in `&lt;top (required)&gt;&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/bin/rails:23:in `load&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/bin/rails:23:in `&lt;main&gt;&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/bin/ruby_executable_hooks:15:in `eval&#39;
	from /Users/nnikolo/.rvm/gems/ruby-2.0.0-p451@railstutorial_rails_4_0/bin/2.2.2.02.02.02.0.2.2.02.222222.2.02.02.0.2.2.022222222222222

It seems the console is not aware of the model. In plain ruby you need to &#39;require&#39; the file containing the class but I thought that the rails console shall automatically load all models. What is going on here?

Content Type	Original Author	Original Content on Stackoverflow
Question	jcollum	View Question on Stackoverflow
Solution 1 - Ruby on-Rails-3	ctcherry	View Answer on Stackoverflow

Can I get the Ruby on Rails console to remember my command history, umm, better?

Ruby on-Rails-3 Problem Overview

Ruby on-Rails-3 Solutions

Solution 1 - Ruby on-Rails-3

How would I render a dynamic definition list using AngularJS?

How do I specify "not equals to" when comparing strings in an XSLT <xsl:if>?

Attributions