QRegExp: include the QRegularExpression porting docs

The docs are moved to:

 qtbase/doc/global/includes/corelib/port-from-qregexp.qdocinc

Remove the old docs and include the docs from qtbase.

Task-number: QTBUG-89702
Pick-to: 6.4 6.3 6.2
Change-Id: Idc2f8cc30e8b104e58b5b0260660495992bbc546
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 1 insertions, 128 deletions

diff --git a/src/core5/text/qregexp.cpp b/src/core5/text/qregexp.cpp
index 9112157..7e27e15 100644
--- a/src/core5/text/qregexp.cpp
+++ b/src/core5/text/qregexp.cpp
@@ -657,134 +657,7 @@ QT_BEGIN_NAMESPACE
 
     \section1 Porting to QRegularExpression
 
-    The QRegularExpression class introduced in Qt 5 is a big improvement upon
-    QRegExp, in terms of APIs offered, supported pattern syntax and speed of
-    execution. The biggest difference is that QRegularExpression simply holds a
-    regular expression, and it's \e{not} modified when a match is requested.
-    Instead, a QRegularExpressionMatch object is returned, in order to check
-    the result of a match and extract the captured substring. The same applies
-    with global matching and QRegularExpressionMatchIterator.
-
-    Other differences are outlined below.
-
-    \section2 Different pattern syntax
-
-    Porting a regular expression from QRegExp to QRegularExpression may require
-    changes to the pattern itself.
-
-    In certain scenarios, QRegExp was too lenient and accepted patterns that
-    are simply invalid when using QRegularExpression. These are somehow easy
-    to detect, because the QRegularExpression objects built with these patterns
-    are not valid (cf. QRegularExpression::isValid()).
-
-    In other cases, a pattern ported from QRegExp to QRegularExpression may
-    silently change semantics. Therefore, it is necessary to review the
-    patterns used. The most notable cases of silent incompatibility are:
-
-    \list
-
-    \li Curly braces are needed in order to use a hexadecimal escape like
-    \c{\xHHHH} with more than 2 digits. A pattern like \c{\x2022} neeeds to
-    be ported to \c{\x{2022}}, or it will match a space (\c{0x20}) followed
-    by the string \c{"22"}. In general, it is highly recommended to always use
-    curly braces with the \c{\x} escape, no matter the amount of digits
-    specified.
-
-    \li A 0-to-n quantification like \c{{,n}} needs to be ported to \c{{0,n}} to
-    preserve semantics. Otherwise, a pattern such as \c{\d{,3}} would
-    actually match a digit followed by the exact string \c{"{,3}"}.
-
-    \li QRegExp by default does Unicode-aware matching, while
-    QRegularExpression requires a separate option; see below for more details.
-
-    \li c{.} in QRegExp does by default match all characters, including the
-    newline character. QRegularExpression excludes the newline character by
-    default. To include the newline character, set the
-    QRegularExpression::DotMatchesEverythingOption pattern option.
-
-    \endlist
-
-    \section2 Porting from QRegExp::exactMatch()
-
-    QRegExp::exactMatch() in Qt 4 served two purposes: it exactly matched
-    a regular expression against a subject string, and it implemented partial
-    matching.
-
-    \section3 Porting from QRegExp's Exact Matching
-
-    Exact matching indicates whether the regular expression matches the entire
-    subject string. For example, the classes yield on the subject string \c{"abc123"}:
-
-    \table
-    \header \li                  \li QRegExp::exactMatch() \li QRegularExpressionMatch::hasMatch()
-    \row    \li \c{"\\d+"}       \li \b false              \li \b true
-    \row    \li \c{"[a-z]+\\d+"} \li \b true               \li \b true
-    \endtable
-
-    Exact matching is not reflected in QRegularExpression. If you want
-    to be sure that the subject string matches the regular expression
-    exactly, you can wrap the pattern using the QRegularExpression::anchoredPattern()
-    function:
-
-    \snippet code/src_corelib_text_qregexp.cpp 21
-
-    \section3 Porting from QRegExp's Partial Matching
-
-    When using QRegExp::exactMatch(), if an exact match was not found, one
-    could still find out how much of the subject string was matched by the
-    regular expression by calling QRegExp::matchedLength(). If the returned length
-    was equal to the subject string's length, then one could conclude that a partial
-    match was found.
-
-    QRegularExpression supports partial matching explicitly by means of the
-    appropriate MatchType.
-
-    \section2 Global matching
-
-    Due to limitations of the QRegExp API it was impossible to implement global
-    matching correctly (that is, like Perl does). In particular, patterns that
-    can match 0 characters (like \c{"a*"}) are problematic.
-
-    QRegularExpression::globalMatch() implements Perl global match correctly, and
-    the returned iterator can be used to examine each result.
-
-    \section2 Unicode properties support
-
-    When using QRegExp, character classes such as \c{\w}, \c{\d}, etc. match
-    characters with the corresponding Unicode property: for instance, \c{\d}
-    matches any character with the Unicode Nd (decimal digit) property.
-
-    Those character classes only match ASCII characters by default when using
-    QRegularExpression: for instance, \c{\d} matches exactly a character in the
-    \c{0-9} ASCII range. It is possible to change this behavior by using the
-    UseUnicodePropertiesOption pattern option.
-
-    \section2 Wildcard matching
-
-    There is no direct way to do wildcard matching in QRegularExpression.
-    However, the wildcardToRegularExpression method is provided to translate
-    glob patterns into a Perl-compatible regular expression that can be used
-    for that purpose.
-
-    \section2 Other pattern syntaxes
-
-    QRegularExpression supports only Perl-compatible regular expressions.
-
-    \section2 Minimal matching
-
-    QRegExp::setMinimal() implemented minimal matching by simply reversing the
-    greediness of the quantifiers (QRegExp did not support lazy quantifiers,
-    like \c{*?}, \c{+?}, etc.). QRegularExpression instead does support greedy,
-    lazy and possessive quantifiers. The InvertedGreedinessOption
-    pattern option can be useful to emulate the effects of QRegExp::setMinimal():
-    if enabled, it inverts the greediness of quantifiers (greedy ones become
-    lazy and vice versa).
-
-    \section2 Caret modes
-
-    The AnchorAtOffsetMatchOption match option can be used to emulate the
-    QRegExp::CaretAtOffset behavior. There is no equivalent for the other
-    QRegExp::CaretMode modes.
+    \include corelib/port-from-qregexp.qdocinc porting-to-qregularexpression
 */
 
 #if defined(Q_OS_VXWORKS) && defined(EOS)