ActionView::Helpers::FormOptionsHelper

Provides a number of methods for turning different kinds of containers into a set of option tags.

The collection_select, select and time_zone_select methods take an options parameter, a hash:

• :include_blank - set to true or a prompt string if the first option element of the select element is a blank. Useful if there is not a default value required for the select element.

  select("post", "category", Post::CATEGORIES, {include_blank: true})
  

  could become:

  <select name="post[category]" id="post_category">
    <option value="">&	          			          		
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