= Erubi

Erubi is a ERB template engine for ruby. It is a simplified fork of Erubis, using
the same basic algorithm, with the following differences:

* Handles postfix conditionals when using escaping (e.g. <tt><%= foo if bar %></tt>)
* Supports frozen_string_literal: true in templates via :freeze option
* Works with ruby's --enable-frozen-string-literal option
* Automatically freezes strings for template text when ruby optimizes it (on ruby 2.1+)
* Escapes ' (apostrophe) when escaping for better XSS protection 
* Has 6x faster escaping on ruby 2.3+ by using cgi/escape
* Has 86% smaller memory footprint
* Does no monkey patching (Erubis adds a method to Kernel)
* Uses an immutable design (all options passed to the constructor, which returns a frozen object)
* Has simpler internals (1 file, <150 lines of code)
* Has an open development model (Erubis doesn't have a public source control repository or bug tracker)
* Is not dead (Erubis hasn't been updated since 2011)

It is not designed with Erubis API compatibility in mind, though most Erubis
ERB syntax works, with the following exceptions:

* No support for <tt><%===</tt> for debug output

= Installation

  gem install erubi

= Source Code

Source code is available on GitHub at https://github.com/jeremyevans/erubi

= Usage

Erubi only has built in support for retrieving the generated source for a
file:

  require 'erubi'
  eval(Erubi::Engine.new(File.read('filename.erb')).src)

Most users are will probably use Erubi via Rails or Tilt.  Erubi is the default
erb template handler in Tilt 2.0.6+ and will be the default template handler in
Rails 5.1+.

== Capturing

Erubi does not support capturing block output into the template by default.
However, it comes with an +erubi/capture_end+ file that supports capturing
via <tt><%|=</tt> and <tt><%|==</tt> tags which are closed with a
<tt><%|</tt> tag:

  <%|= form do %>
    <input>
  <%| end %>

This offers similar functionality to that offered by Rails' <tt><%=</tt>
tags, but without the corner cases with that approach (which are due to
attempting to parse ruby code via a regexp).  Similar to the <tt><%=</tt>
and <tt><%==</tt> tags, <tt><%|=</tt> captures by default and
<tt><%|==</tt> captures and escapes by default, but this can be reversed
via the +:escape_capture+ or +:escape+ options.

To use the capture_end support with tilt:

  require 'tilt'
  require 'erubi/capture_end'
  Tilt.new("filename.erb", :engine_class=>Erubi::CaptureEndEngine).render

= Reporting Bugs

The bug tracker is located at https://github.com/jeremyevans/erubi/issues

= License

MIT

= Authors

Jeremy Evans <code@jeremyevans.net>
kuwata-lab.com