with: Controls DTML variable look up

  The 'with' tag pushes an object onto the DTML namespace. Variables
  will be looked up in the pushed object first.

  Syntax

    'with' tag syntax::

      <dtml-with Variable|expr="Expression">
      </dtml-with>

    The 'with' tag is a block tag. It pushes the named variable or
    variable expression onto the DTML namespace for the duration of
    the 'with' block. Thus names are looked up in the pushed object
    first. 

  Attributes

    only -- Limits the DTML namespace to only include the one defined
    in the 'with' tag.

    mapping -- Indicates that the variable or expression is a mapping
    object. This ensures that variables are looked up correctly in the
    mapping object.

  Examples

    Looking up a variable in the REQUEST::

      <dtml-with REQUEST only>
        <dtml-if id>
          <dtml-var id>
        <dtml-else>
          'id' was not in the request.
        </dtml-if>
      </dtml-with>

    Pushing the first child on the DTML namespace::

      <dtml-with expr="objectValues()[0]">
        First child's id: <dtml-var id>
      </dtml-with>

  See Also

    "let tag":dtml-let.stx