    class
    	DATE_VALIDITY_CHECKER

    General
    	cluster: time
    	description: "Facility routines to check the validity of DATEs"

    Ancestors
    	ANY
    	DATE_CONSTANTS
    	DATE_VALUE

    Queries
    	compact_date_valid (c_d: INTEGER_32): BOOLEAN
    	date_valid (s, code_string: STRING_8): BOOLEAN
    	date_valid_default (s: STRING_8): BOOLEAN
    	date_valid_default_with_base (s: STRING_8; base: INTEGER_32): BOOLEAN
    	date_valid_with_base (s, code_string: STRING_8; base: INTEGER_32): BOOLEAN
    	is_correct_date (y, m, d: INTEGER_32): BOOLEAN
    	ordered_compact_date_valid (c_d: INTEGER_32): BOOLEAN