content: /* 
   * Kodkod -- Copyright (c) 2005-present, Emina Torlak
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  package kodkod.ast.operator;
  
  /**
   * Represents the multiplicity of an expression
   * in a {@link kodkod.ast.MultiplicityFormula} or
   * the multiplicity of a variable in a {@link kodkod.ast.Decl }.
   * 
   * @author Emina Torlak
   */
  public enum Multiplicity {
  	/** <tt>no expr</tt>: expr contains no elements.  The 'no' multiplicity can only be used in a multiplicity formula. */
      NO { public String toString() { return "no"; }},
      /** <tt>lone expr</tt>: expr contains at most one element. */
      LONE { public String toString() { return "lone"; }},
      /** <tt>one expr</tt>: expr contains exactly one element. */
      ONE { public String toString() { return "one"; }},
      /** <tt>some expr</tt>: expr contains at least one element. */
      SOME { public String toString() { return "some"; }},
      /** <tt>v: set expr</tt>: v is a subset of expr.  The 'set' multiplicity can only be used in a declaration. */
      SET { public String toString() { return "set"; }}
  }