truncate

Method description from Rails 2.0

If text is longer than length, text will be truncated to the length of length (defaults to 30) and the last characters will be replaced with the truncate_string (defaults to “…”).

Examples

truncate("Once upon a time in a world far far away", 14)
# => Once upon a...

truncate("Once upon a time in a world far far away")
# => Once upon a time in a world f...

truncate("And they found that many people were sleeping better.", 25, "(clipped)")
# => And they found that many (clipped)

truncate("And they found that many people were sleeping better.", 15, "... (continued)")
# => And they found... (continued)

Incompatible with Ruby 1.8.7

If using Rails < 2.2 with Ruby 1.8.7, calling truncate will result in the following error:

undefined method `length' for #<Enumerable::Enumerator:0xb74f952c>

The workaround (other than upgrading to Rails 2.2 or higher), is to overwrite the truncate method, by inserting the following at the end of environment.rb (or where it will be called on startup):

module ActionView
  module Helpers
    module TextHelper
      def truncate(text, length = 30, truncate_string = "...")
        if text.nil? then return end
        l = length - truncate_string.chars.to_a.size
        (text.chars.to_a.size > length ? text.chars.to_a[0...l].join + truncate_string : text).to_s
      end
    end
  end
end

Deprecation warning for using options without hash

As of Rails 2.2.0, truncate gives a Deprecation warning if you don’t use a hash for the options. Ex:

The old way

truncate(project.description, 100, "... Read More")

The warning

DEPRECATION WARNING: truncate takes an option hash instead of separate length and omission arguments.

The new way

truncate(project.description, :ommision => "... Read More", :length => 100)