///////////////////////////////////////////////////////////////////////////// // Name: regex.h // Purpose: interface of wxRegEx // Author: wxWidgets team // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// /** @anchor wxRE_FLAGS Flags for regex compilation to be used with wxRegEx::Compile(). */ enum { /** Use extended regex syntax. */ wxRE_EXTENDED = 0, /** Use advanced RE syntax (built-in regex only). */ wxRE_ADVANCED = 1, /** Use basic RE syntax. */ wxRE_BASIC = 2, /** Ignore case in match. */ wxRE_ICASE = 4, /** Only check match, don't set back references. */ wxRE_NOSUB = 8, /** If not set, treat '\n' as an ordinary character, otherwise it is special: it is not matched by '.' and '^' and '$' always match after/before it regardless of the setting of wxRE_NOT[BE]OL. */ wxRE_NEWLINE = 16, /** Default flags.*/ wxRE_DEFAULT = wxRE_EXTENDED }; /** @anchor wxRE_NOT_FLAGS Flags for regex matching to be used with wxRegEx::Matches(). These flags are mainly useful when doing several matches in a long string to prevent erroneous matches for '^' and '$': */ enum { /** '^' doesn't match at the start of line. */ wxRE_NOTBOL = 32, /** '$' doesn't match at the end of line. */ wxRE_NOTEOL = 64 }; /** @class wxRegEx wxRegEx represents a regular expression. This class provides support for regular expressions matching and also replacement. It is built on top of either the system library (if it has support for POSIX regular expressions - which is the case of the most modern Unices) or uses the built in Henry Spencer's library. Henry Spencer would appreciate being given credit in the documentation of software which uses his library, but that is not a requirement. Regular expressions, as defined by POSIX, come in two flavours: @e extended and @e basic. The builtin library also adds a third flavour of expression @ref overview_resyntax "advanced", which is not available when using the system library. Unicode is fully supported only when using the builtin library. When using the system library in Unicode mode, the expressions and data are translated to the default 8-bit encoding before being passed to the library. On platforms where a system library is available, the default is to use the builtin library for Unicode builds, and the system library otherwise. It is possible to use the other if preferred by selecting it when building the wxWidgets. @library{wxbase} @category{data} Example: A (bad) example of processing some text containing email addresses (the example is bad because the real email addresses can have more complicated form than @c user@host.net): @code wxString originalText = "This is some text with foo@example.com and bar@example.com"; // Regex. to match an email address and extract its subparts. wxRegEx reEmail("([^@ -]+)@([[:alnum:]_]+).([[:alnum:]]{2,4})"); wxString processText = originalText; while ( reEmail.Matches(processText) ) { // Find the size of the first match and print it. size_t start, len; reEmail.GetMatch(&start, &len, 0); std::cout << "Email: " << reEmail.GetMatch(processText, 0) << std::endl; // Print the submatches. std::cout << "Name: " << reEmail.GetMatch(processText, 1) << std::endl; std::cout << "Domain: " << reEmail.GetMatch(processText, 2) << std::endl; std::cout << "TLD: " << reEmail.GetMatch(processText, 3) << std::endl; // Process the remainder of the text if there is any. processText = processText.Mid (start + len); } // Or this will replace all names with "HIDDEN". size_t count = reEmail.ReplaceAll(&originalText, "HIDDEN@\\2.\\3"); std::cout << "text now contains " << count << " hidden addresses" << std::endl; std::cout << originalText << std::endl; @endcode */ class wxRegEx { public: /** Default constructor: use Compile() later. */ wxRegEx(); /** Create and compile the regular expression, use IsValid() to test for compilation errors. As for the flags, please see @ref wxRE_FLAGS. */ wxRegEx(const wxString& expr, int flags = wxRE_DEFAULT); /** Destructor. It's not virtual, don't derive from this class. */ ~wxRegEx(); /** Compile the string into regular expression, return @true if ok or @false if string has a syntax error. As for the flags, please see @ref wxRE_FLAGS. */ bool Compile(const wxString& pattern, int flags = wxRE_DEFAULT); /** Get the start index and the length of the match of the expression (if @a index is 0) or a bracketed subexpression (@a index different from 0). May only be called after successful call to Matches() and only if @c wxRE_NOSUB was @b not used in Compile(). Returns @false if no match or if an error occurred. */ bool GetMatch(size_t* start, size_t* len, size_t index = 0) const; /** Returns the part of string corresponding to the match where index is interpreted as above. Empty string is returned if match failed. May only be called after successful call to Matches() and only if @c wxRE_NOSUB was @b not used in Compile(). */ wxString GetMatch(const wxString& text, size_t index = 0) const; /** Returns the size of the array of matches, i.e.\ the number of bracketed subexpressions plus one for the expression itself, or 0 on error. May only be called after successful call to Compile(). and only if @c wxRE_NOSUB was @b not used. */ size_t GetMatchCount() const; /** Return @true if this is a valid compiled regular expression, @false otherwise. */ bool IsValid() const; //@{ /** Matches the precompiled regular expression against the string @a text, returns @true if matches and @false otherwise. @e Flags may be combination of @c wxRE_NOTBOL and @c wxRE_NOTEOL, see @ref wxRE_NOT_FLAGS. Some regex libraries assume that the text given is null terminated, while others require the length be given as a separate parameter. Therefore for maximum portability assume that @a text cannot contain embedded nulls. When the Matches(const wxChar *text, int flags = 0) form is used, a wxStrlen() will be done internally if the regex library requires the length. When using Matches() in a loop the Matches(text, flags, len) form can be used instead, making it possible to avoid a wxStrlen() inside the loop. May only be called after successful call to Compile(). */ bool Matches(const wxChar* text, int flags = 0) const; bool Matches(const wxChar* text, int flags, size_t len) const; //@} /** Matches the precompiled regular expression against the string @a text, returns @true if matches and @false otherwise. @e Flags may be combination of @c wxRE_NOTBOL and @c wxRE_NOTEOL, see @ref wxRE_NOT_FLAGS. May only be called after successful call to Compile(). */ bool Matches(const wxString& text, int flags = 0) const; /** Replaces the current regular expression in the string pointed to by @a text, with the text in @a replacement and return number of matches replaced (maybe 0 if none found) or -1 on error. The replacement text may contain back references @c \\number which will be replaced with the value of the corresponding subexpression in the pattern match. @c \\0 corresponds to the entire match and @c \& is a synonym for it. Backslash may be used to quote itself or @c \& character. @a maxMatches may be used to limit the number of replacements made, setting it to 1, for example, will only replace first occurrence (if any) of the pattern in the text while default value of 0 means replace all. */ int Replace(wxString* text, const wxString& replacement, size_t maxMatches = 0) const; /** Replace all occurrences: this is actually a synonym for Replace(). @see ReplaceFirst() */ int ReplaceAll(wxString* text, const wxString& replacement) const; /** Replace the first occurrence. */ int ReplaceFirst(wxString* text, const wxString& replacement) const; };