each 
Purpose
Uses the Groovy JDK each method to iterate over each element of the specified object.Examples
<g:each in="${books}">
     <p>Title: ${it.title}</p>
     <p>Author: ${it.author}</p>
</g:each> With a named item:<g:each var="book" in="${books}">
     <p>Title: ${book.title}</p>
     <p>Author: ${book.author}</p>
</g:each> With a range literal - note how the literal must be enclosed in parentheses:<ul>
  <g:each var="i" in="${ (0..<100) }">
    <li>Item ${i}</li>
  </g:each>
</ul> Another example, where a named item is necessary (otherwise the access to the title property will fail):<g:each in="${itemList}" var="item">
	<g:link action="show" id="${item.id}">${item.title}</g:link>
</g:each> Using the status parameter to alternate the coloring of a table's rows:<tbody>
  <g:each status="i" in="${itemList}" var="item">
    
    <tr class="${ (i % 2) == 0 ? 'a' : 'b'}">
      <td>${item.id?.encodeAsHTML()}</td>
      <td>${item.parentId?.encodeAsHTML()}</td>
      <td>${item.type?.encodeAsHTML()}</td>
      <td>${item.status?.encodeAsHTML()}</td>
    </tr>
  </g:each>
</tbody> 
Description
Attributes
in - The object to iterate over 
status (optional) - The name of a variable to store the iteration index in. For the first iteration this variable has a value of 0, for the next, 1, and so on. If this parameter is used, then var is required. 
var (optional) - The name of the item, defaults to "it". 
Note that var attribute must be specified when the iterator value is to be used from within the body of a GSP Dynamic Tag, such as in <g:link>.