qstaticlatin1stringmatcher.qdoc

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// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
// Qt-Security score:insignificant reason:docs
 
/*! \class QStaticLatin1StringMatcher
    \inmodule QtCore
    \brief The QStaticLatin1StringMatcher class is a compile-time version
    of QLatin1StringMatcher.
 
    \since 6.7
    \ingroup tools
    \ingroup string-processing
 
    QStaticLatin1StringMatcher<CS, N> is a template class where \a CS is
    the Qt::CaseSensitivity to use for matching and \a N is the length of the
    pattern to search for (including the null terminator for string literals).
 
    This class is useful when your code needs to search efficiently
    in Latin-1 strings for a substring that's known at compile-time.
    This is common, for example, in parsers. Using a matcher
    object's indexIn() is faster than using the indexOf() member method of
    the string you are searching in, especially when the string to
    be found will be searched for repeatedly or within a large
    Latin-1 string that may contain many matches to prefixes of the
    substring to be found.
 
    Unlike QLatin1StringMatcher, this class calculates the internal
    representation at \e{compile-time}, so it can be beneficial even if you
    are doing one-off Latin-1 string matches.
 
    Create the QStaticLatin1StringMatcher by calling
    qMakeStaticCaseSensitiveLatin1StringMatcher() or
    qMakeStaticCaseInsensitiveLatin1StringMatcher() passing the Latin-1
    string to search for as a C string literal. Store the return value of
    that function in a \c{static constexpr auto} variable, so you don't
    need to pass the \c{N} template parameter explicitly.
 
    Then call indexIn() on the QLatin1StringView in which you want to search,
    just like with QLatin1StringMatcher.
 
    Since this class is designed to do all the up-front calculations at
    compile-time, it does not offer setPattern() or setCaseSensitivity()
    methods.
 
    \note INTEGRITY operating system is currently not supported.
 
    \sa QLatin1StringMatcher, QStaticByteArrayMatcher, QByteArrayMatcher
*/
 
/*!
    \fn template<Qt::CaseSensitivity CS, size_t N> constexpr qsizetype QStaticLatin1StringMatcher<CS, N>::indexIn(QLatin1StringView haystack, qsizetype from) const
    \fn template<Qt::CaseSensitivity CS, size_t N> constexpr qsizetype QStaticLatin1StringMatcher<CS, N>::indexIn(QStringView haystack, qsizetype from) const
 
    Searches the QLatin1StringView \a haystack, from byte position \a from
    (default 0, i.e. from the first byte), for QLatin1StringView pattern()
    that was set in the constructor. Using the case sensitivity that was also
    set in the constructor.
 
    Returns the position where the pattern() matched in \a haystack, or -1 if no match was found.
*/
 
/*!
    \fn template<size_t N> constexpr auto qMakeStaticCaseSensitiveLatin1StringMatcher(const char
   (&patternToMatch)[N])
 
    \since 6.7
    \relates QStaticLatin1StringMatcher
 
    Return a QStaticLatin1StringMatcher with the correct \a N determined
    automatically from the \a patternToMatch passed, and with case sensitivity.
 
    To take full advantage of this function, assign the result to a
    \c{static constexpr auto} variable:
 
    \snippet code/src_corelib_text_qstaticlatin1stringmatcher.cpp 0
*/
 
/*!
    \fn template<size_t N> constexpr auto qMakeStaticCaseInsensitiveLatin1StringMatcher(const char
   (&patternToMatch)[N])
 
    \since 6.7
    \relates QStaticLatin1StringMatcher
 
    Return a QStaticLatin1StringMatcher with the correct \a N determined
    automatically from the \a patternToMatch passed, and without case sensitivity.
 
    To take full advantage of this function, assign the result to a
    \c{static constexpr auto} variable:
 
    \snippet code/src_corelib_text_qstaticlatin1stringmatcher.cpp 1
*/