Getting started with Ruby Language Casting (type conversion)Arrays Classes Hashes Blocks and Procs and Lambdas Inheritance Control Flow Strings Symbols Exceptions Thread Methods method_missing Numbers Iteration Regular Expressions and Regex Based Operations Comparable Gem Usage Design Patterns and Idioms in Ruby Loading Source Files Range Comments Operators Operators Special Constants in Ruby Modules Ruby Version Manager Gem Creation/Management Constants Variable Scope and Visibility rbenv Environment Variables Singleton Class File and I/O Operations Time Queue Destructuring IRB Enumerators C Extensions Struct Metaprogramming Dynamic Evaluation instance_eval Message Passing Keyword Arguments DateTime Truthiness JSON with Ruby Implicit Receivers and Understanding Self Monkey Patching in Ruby Introspection Monkey Patching in Ruby Refinements Monkey Patching in Ruby Catching Exceptions with Begin / Rescue Command Line Apps Debugging Pure RSpec JSON API testing Recursion in Ruby Installation ERB Introspection in Ruby Generate a random number Getting started with Hanami OptionParser Splat operator (*)Multidimensional Arrays Enumerable in Ruby Ruby Access Modifiers Operating System or Shell commands

ERB

Remarks:

Conventions:

ERB as a template: Abstract business logic into accompanied helper code, and keep your ERB templates clean and readable for people without Ruby knowledge.
Append files with .erb: e.g. .js.erb, .html.erb, .css.erb, etc.

Parsing ERB

This example is filtered text from an IRB session.

=> require 'erb'
=> input = <<-HEREDOC
<ul>
<% (0..10).each do |i| %>
    <%# This is a comment %>
    <li><%= i %> is <%= i.even? ? 'even' : 'odd' %>.</li>
<% end %>
</ul>
HEREDOC

=> parser = ERB.new(input)
=> output = parser.result
=> print output
<ul>


    <li>0 is even.</li>


    <li>1 is odd.</li>


    <li>2 is even.</li>


    <li>3 is odd.</li>


    <li>4 is even.</li>


    <li>5 is odd.</li>


    <li>6 is even.</li>


    <li>7 is odd.</li>


    <li>8 is even.</li>


    <li>9 is odd.</li>


    <li>10 is even.</li>

</ul>

Syntax:

<% number = rand(10) %> this code will be evaluated
<%= number %> this code will be evaluated and inserted into the output
<%# comment text %> this comment will not be evaluated

Contributors

Topic Id: 8145

Example Ids: 26210

This site is not affiliated with any of the contributors.