michael@0: /*
michael@0: *******************************************************************************
michael@0: *   Copyright (C) 2010-2012, International Business Machines
michael@0: *   Corporation and others.  All Rights Reserved.
michael@0: *******************************************************************************
michael@0: *   file name:  udicttrie.h
michael@0: *   encoding:   US-ASCII
michael@0: *   tab size:   8 (not used)
michael@0: *   indentation:4
michael@0: *
michael@0: *   created on: 2010dec17
michael@0: *   created by: Markus W. Scherer
michael@0: */
michael@0: 
michael@0: #ifndef __USTRINGTRIE_H__
michael@0: #define __USTRINGTRIE_H__
michael@0: 
michael@0: /**
michael@0:  * \file
michael@0:  * \brief C API: Helper definitions for dictionary trie APIs.
michael@0:  */
michael@0: 
michael@0: #include "unicode/utypes.h"
michael@0: 
michael@0: 
michael@0: /**
michael@0:  * Return values for BytesTrie::next(), UCharsTrie::next() and similar methods.
michael@0:  * @see USTRINGTRIE_MATCHES
michael@0:  * @see USTRINGTRIE_HAS_VALUE
michael@0:  * @see USTRINGTRIE_HAS_NEXT
michael@0:  * @stable ICU 4.8
michael@0:  */
michael@0: enum UStringTrieResult {
michael@0:     /**
michael@0:      * The input unit(s) did not continue a matching string.
michael@0:      * Once current()/next() return USTRINGTRIE_NO_MATCH,
michael@0:      * all further calls to current()/next() will also return USTRINGTRIE_NO_MATCH,
michael@0:      * until the trie is reset to its original state or to a saved state.
michael@0:      * @stable ICU 4.8
michael@0:      */
michael@0:     USTRINGTRIE_NO_MATCH,
michael@0:     /**
michael@0:      * The input unit(s) continued a matching string
michael@0:      * but there is no value for the string so far.
michael@0:      * (It is a prefix of a longer string.)
michael@0:      * @stable ICU 4.8
michael@0:      */
michael@0:     USTRINGTRIE_NO_VALUE,
michael@0:     /**
michael@0:      * The input unit(s) continued a matching string
michael@0:      * and there is a value for the string so far.
michael@0:      * This value will be returned by getValue().
michael@0:      * No further input byte/unit can continue a matching string.
michael@0:      * @stable ICU 4.8
michael@0:      */
michael@0:     USTRINGTRIE_FINAL_VALUE,
michael@0:     /**
michael@0:      * The input unit(s) continued a matching string
michael@0:      * and there is a value for the string so far.
michael@0:      * This value will be returned by getValue().
michael@0:      * Another input byte/unit can continue a matching string.
michael@0:      * @stable ICU 4.8
michael@0:      */
michael@0:     USTRINGTRIE_INTERMEDIATE_VALUE
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Same as (result!=USTRINGTRIE_NO_MATCH).
michael@0:  * @param result A result from BytesTrie::first(), UCharsTrie::next() etc.
michael@0:  * @return true if the input bytes/units so far are part of a matching string/byte sequence.
michael@0:  * @stable ICU 4.8
michael@0:  */
michael@0: #define USTRINGTRIE_MATCHES(result) ((result)!=USTRINGTRIE_NO_MATCH)
michael@0: 
michael@0: /**
michael@0:  * Equivalent to (result==USTRINGTRIE_INTERMEDIATE_VALUE || result==USTRINGTRIE_FINAL_VALUE) but
michael@0:  * this macro evaluates result exactly once.
michael@0:  * @param result A result from BytesTrie::first(), UCharsTrie::next() etc.
michael@0:  * @return true if there is a value for the input bytes/units so far.
michael@0:  * @see BytesTrie::getValue
michael@0:  * @see UCharsTrie::getValue
michael@0:  * @stable ICU 4.8
michael@0:  */
michael@0: #define USTRINGTRIE_HAS_VALUE(result) ((result)>=USTRINGTRIE_FINAL_VALUE)
michael@0: 
michael@0: /**
michael@0:  * Equivalent to (result==USTRINGTRIE_NO_VALUE || result==USTRINGTRIE_INTERMEDIATE_VALUE) but
michael@0:  * this macro evaluates result exactly once.
michael@0:  * @param result A result from BytesTrie::first(), UCharsTrie::next() etc.
michael@0:  * @return true if another input byte/unit can continue a matching string.
michael@0:  * @stable ICU 4.8
michael@0:  */
michael@0: #define USTRINGTRIE_HAS_NEXT(result) ((result)&1)
michael@0: 
michael@0: #endif  /* __USTRINGTRIE_H__ */