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  <xs:complexType name="ParamOptions">

    <xs:annotation>

      <xs:documentation xml:lang="en"><![CDATA[

See [/tools/extract/liftOver_wrapper.xml](https://github.com/galaxyproject/galaxy/blob/master/tools/extract/liftOver_wrapper.xml)

for an example of how to use this tag set. This tag set is optionally contained

within the ``<param>`` tag when the ``type`` attribute value is ``select`` or

``data`` and used to dynamically generated lists of options. This tag set

dynamically creates a list of options whose values can be

obtained from a predefined file stored locally or a dataset selected from the

current history.

``data`` and used to dynamically generated lists of options.

For data parameters it can only be used to restrict inputs to datasets having

the same ``dbkey`` like another input by using a ``data_meta`` filter. See for

instance here: [/tools/maf/interval2maf.xml](https://github.com/galaxyproject/galaxy/blob/master/tools/maf/interval2maf.xml)

For select parameters this tag set dynamically creates a list of options whose

values can be obtained from a predefined file stored locally or a dataset

selected from the current history.

There are at least five basic ways to use this tag - four of these correspond to

a ``from_XXX`` attribute on the ``options`` directive and the other is to