class add_constraint:
    """ Generates a partial SQL command to add a FK to a table """

    def __init__( self, constraint ):
        self.constraint = constraint

    def apply_to_table( self, table ):
        """ Adds the constraint to the table

        :param table: The table to add the constraint to
        :param type: mygrations.formats.mysql.definitions.table
        """
        table.add_constraint( self.constraint )

    def __str__( self ):
        return 'ADD %s' % str( self.constraint )
