CODEWITHSUNDEEP
ruby-on-railsruby
user6175355
user6175355

Reputation:

Purpose of %w in ruby on rails

I see in routes.rb like this

%w( about mission path standard getting_started welcome infection instruction implementation ).each do |page|
    get page, to: "pages##{page}"
end

And when I see home controller , it doesn't have nay actions which list above. But the link works properly.

I want to know what these lines of codes do?

Upvotes: 0

Views: 370

Answers (5)

Bharat soni
Bharat soni

Reputation: 2786

%w( about mission path standard getting_started welcome infection instruction implementation ).each do |page|
    get page, to: "pages##{page}"
end

The above code is defining actions which belong to the pages controller and not the home controller.

Hope that information help you to figure out the things.

Upvotes: -1

Aleks
Aleks

Reputation: 5380

To my understanding the actual question is how is this working when no actions are defined in home controller.

The route you are describing just defines a number of different actions that can be run against your home controller, like about, mission etc.

In order for those pages to be displayed you only need a relevant view in app/views/pages/about.html.erb in order for it to be displayed.

There is no need to define actions in controller like def about to display views. You would need to define them ONLY if you want to set some variables for them to be displayed in the view like @my_name, but by definition you don't need to have controller actions in order to display them

Upvotes: 0

Nitesh
Nitesh

Reputation: 285

%w( about mission path standard getting_started welcome infection instruction implementation ).each do |page|
    get page, to: "pages##{page}"
end

The code works like: %w(foo bar)is a shortcut for array["foo", "bar"] 

.each do |page|

It loops each element such as in 1st loop the value of page = "foo" 

get page, to: "pages##{page}"

This line will become 

get foo, to: "pages#foo"

when user hits /foo you will be redirected to foo action of pages controller, this will be same for other elements too.

Thus, this makes easy to define routes for all the elements in %w( )

Upvotes: 4

mbugowski
mbugowski

Reputation: 11

If it works fine, then maybe you should look for the page controller, not the home controller.

part:

%w( about mission path standard getting_started welcome infection instruction implementation )

%w( - works only for array of strings and is just another way to write:

['about', 'mission', 'path', 'standard', 'getting_started', 'welcome', 'infection', 'instruction', 'implementation']

It's more convenient, because you don't have to worry about commas and other, just separate items of array by space.

If you iterate (.each) this and in block you do get page, to: "pages##{page}" it does for every item:

get 'about', to: "pages#about"

get 'mission', to: "pages#mission"

and so on. And in this case controller is 'pages', and action is 'about' etc.

Here is more about %w: http://ruby-doc.org/core-2.2.3/doc/syntax/literals_rdoc.html#label-Percent+Strings

About routing: http://guides.rubyonrails.org/routing.html#singular-resources

Upvotes: 1

dennis
dennis

Reputation: 2020

the %w is a ruby processor which splits the inputted string at the whitespace and outputs an array.

then it applies the 

get page, to: "pages##{page}"

to the specific entries in the array.

The reason you don't see the actions defined in the PagesController is because the controller actions would probably be empty since they are probably semi-static pages.

In this case the Ruby on Rails application only requires the correct views to be in place and no specific action to be defined.

Upvotes: 0

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