String to Boolean in Ruby

2012-07-02 · 1 min read

When parsing data you may end up with string representations of various data types. For example, Boolean value might be represented as "true", "t", "yes", "y" or "1".

In order to resolve that problem with Ruby I chosed to do a quick hack. The following code adds new behaviour to String class. Such approach is called Monkey Patching. It should be used with caution as it can result in hard to track down errors.

class String
  def to_bool
    return true if self =~ (/^(true|t|yes|y|1)$/i)
    return false if self.empty? || self =~ (/^(false|f|no|n|0)$/i)
    raise "invalid value: #{self}"

To make it work with Rails you should add this snippet as a initializer inside config / initializers directory.