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/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2006-2010, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */



package scala

/** 
 *    A marker for annotations that, when applied to a type,
 *    should be treated as a constraint on the annotated type.
 *    A proper constraint should restrict the type based only
 *    on information mentioned within the type.  A Scala compiler
 *    can use this assumption to rewrite the contents of the
 *    constraint as necessary.  To contrast, a type annotation
 *    whose meaning depends on the context where it is written
 *    down is not a proper constrained type, and this marker
 *    should not be applied.  A Scala compiler will drop such
 *    annotations in cases where it would rewrite a type constraint.
 *  
 *
 *  @author  Lex Spoon
 *  @version 1.1, 2007-11-5
 *  @since   2.6
 */
trait TypeConstraint extends Annotation