////
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////

You can also create logical tags where the body of the tag is only output once a set of conditions have been met. An example of this may be a set of security tags:

[source,groovy]
----
def isAdmin(Map attrs, Closure body) {
    def user = attrs.user
    if (user && checkUserPrivs(user)) {
        out << body()
    }
}
----

The tag above checks if the user is an administrator and only outputs the body content if he/she has the correct set of access privileges:

[source,xml]
----
<g:isAdmin user="${myUser}">
    // some restricted content
</g:isAdmin>
----
