// Note: The externs defined in this file are proposed to become part
// of the public pna.p4 include file.

extern ExactMap<K, V, E> {
    /**
     * Create a table with match kinds all 'exact' and the specified
     * size (number of entries).  The default value returned when a
     * lookup experiences a miss is given by default_value.
     */
    ExactMap(int size, V default_value);

    /**
     * The same as the constructor with an explicit default_value,
     * except the default_value is the default value for the type V as
     * defined in the section "Default values" of the P4_16 language
     * specification.
     */
    ExactMap(int size);

    /**
     * Create a table with match kinds all 'exact' and the specified
     * size (number of entries).  The default value returned when a
     * lookup experiences a miss is given by default_value.
     * const_entries is a list of entries, similar to the 'const
     * entries' table property for tables.
     *
     * Example where key and value types are bit<W>:

     *     ExactMap<bit<8>, bit<16>, _>(
     *         size = 1024,
     *         const_entries = {
     *             {5, 10},  // key 5, value 10
     *             {6, 27},  // key 6, value 27
     *             {10, 2}   // key 10, value 2
     *         },
     *         default_value = 42)  // default value returned for all other keys
     *     vemap;

     */
    ExactMap(int size, E const_entries, V default_value);

    /**
     * Look up the key in the table.  Always hits, so always returns a
     * value of type V.
     */
    V lookup(in K key);
}

extern TernaryMap<K, V, E> {
    /**
     * Create a table with match kinds all 'ternary' and the specified
     * size (number of entries).  The default value returned when a
     * lookup experiences a miss is given by default_value.
     */
    TernaryMap(int size, V default_value);

    /**
     * The same as the constructor with an explicit default_value,
     * except the default_value is the default value for the type V as
     * defined in the section "Default values" of the P4_16 language
     * specification.
     */
    TernaryMap(int size);

    /**
     * Create a table with match kinds all 'ternary' and the specified
     * size (number of entries).  The default value returned when a
     * lookup experiences a miss is given by default_value.
     * const_entries is a list of entries, similar to the 'const
     * entries' table property for tables.
     *
     * Example where key and value types are bit<W>:

     *     TernaryMap<bit<24>, bit<16>, _>(
     *         size = 1024,
     *         const_entries = {
     *             {{5, 0xffffff}, 10},  // ternary key with value 5, mask 0xffffff (exact match on least significant 24 bits), value 10
     *             {{6, 0xffffff}, 27},  // ternary key with value 6, mask 0xffffff, value 27
     *             {{10, 0x00ffff}, 2}   // ternary key with value 10, mask 0x00ffff (exact match on least significant 16 bits, wildcard on bits [23:16]), value 2
     *         },
     *         default_value = 42)  // default value returned for all other keys
     *     vemap;

     */
    TernaryMap(int size, E const_entries, V default_value);

    /**
     * Look up the key in the table.  Always hits, so always returns a
     * value of type V.
     */
    V lookup(in K key);
}