wxWidgets/include/wx/unichar.h
2007-07-20 01:10:22 +00:00

319 lines
12 KiB
C++

///////////////////////////////////////////////////////////////////////////////
// Name: wx/unichar.h
// Purpose: wxUniChar and wxUniCharRef classes
// Author: Vaclav Slavik
// Created: 2007-03-19
// RCS-ID: $Id$
// Copyright: (c) 2007 REA Elektronik GmbH
// Licence: wxWindows licence
///////////////////////////////////////////////////////////////////////////////
#ifndef _WX_UNICHAR_H_
#define _WX_UNICHAR_H_
#include "wx/defs.h"
#include "wx/chartype.h"
#include "wx/stringimpl.h"
class WXDLLIMPEXP_FWD_BASE wxUniCharRef;
class WXDLLIMPEXP_FWD_BASE wxStringIteratorNode;
// This class represents single Unicode character. It can be converted to
// and from char or wchar_t and implements commonly used character operations.
class WXDLLIMPEXP_BASE wxUniChar
{
public:
// NB: this is not wchar_t on purpose, it needs to represent the entire
// Unicode code points range and wchar_t may be too small for that
// (e.g. on Win32 where wchar_t* is encoded in UTF-16)
typedef wxUint32 value_type;
wxUniChar() : m_value(0) {}
// Create the character from 8bit character value encoded in the current
// locale's charset.
wxUniChar(char c) { m_value = From8bit(c); }
wxUniChar(unsigned char c) { m_value = From8bit((char)c); }
// Create the character from a wchar_t character value.
#if wxWCHAR_T_IS_REAL_TYPE
wxUniChar(wchar_t c) { m_value = c; }
#endif
wxUniChar(int c) { m_value = c; }
wxUniChar(unsigned int c) { m_value = c; }
wxUniChar(long int c) { m_value = c; }
wxUniChar(unsigned long int c) { m_value = c; }
wxUniChar(short int c) { m_value = c; }
wxUniChar(unsigned short int c) { m_value = c; }
wxUniChar(const wxUniCharRef& c);
// Returns Unicode code point value of the character
value_type GetValue() const { return m_value; }
#if wxUSE_UNICODE_UTF8
// buffer for single UTF-8 character
struct Utf8CharBuffer
{
char data[5];
operator const char*() const { return data; }
};
// returns the character encoded as UTF-8
// (NB: implemented in stringops.cpp)
Utf8CharBuffer AsUTF8() const;
#endif // wxUSE_UNICODE_UTF8
// Returns true if the character is an ASCII character:
bool IsAscii() const { return m_value < 0x80; }
// Conversions to char and wchar_t types: all of those are needed to be
// able to pass wxUniChars to verious standard narrow and wide character
// functions
operator char() const { return To8bit(m_value); }
operator unsigned char() const { return (unsigned char)To8bit(m_value); }
#if wxWCHAR_T_IS_REAL_TYPE
operator wchar_t() const { return (wchar_t)m_value; }
#endif
operator int() const { return (int)m_value; }
operator unsigned int() const { return (unsigned int)m_value; }
operator long int() const { return (long int)m_value; }
operator unsigned long int() const { return (unsigned long)m_value; }
operator short int() const { return (short int)m_value; }
operator unsigned short int() const { return (unsigned short int)m_value; }
// We need this operator for the "*p" part of expressions like "for (
// const_iterator p = begin() + nStart; *p; ++p )". In this case,
// compilation would fail without it because the conversion to bool would
// be ambiguous (there are all these int types conversions...). (And adding
// operator unspecified_bool_type() would only makes the ambiguity worse.)
operator bool() const { return m_value != 0; }
bool operator!() const { return !((bool)*this); }
// And this one is needed by some (not all, but not using ifdefs makes the
// code easier) compilers to parse "str[0] && *p" successfully
bool operator&&(bool v) const { return (bool)*this && v; }
// Assignment operators:
wxUniChar& operator=(const wxUniChar& c) { m_value = c.m_value; return *this; }
wxUniChar& operator=(const wxUniCharRef& c);
wxUniChar& operator=(char c) { m_value = From8bit(c); return *this; }
wxUniChar& operator=(unsigned char c) { m_value = From8bit((char)c); return *this; }
#if wxWCHAR_T_IS_REAL_TYPE
wxUniChar& operator=(wchar_t c) { m_value = c; return *this; }
#endif
wxUniChar& operator=(int c) { m_value = c; return *this; }
wxUniChar& operator=(unsigned int c) { m_value = c; return *this; }
wxUniChar& operator=(long int c) { m_value = c; return *this; }
wxUniChar& operator=(unsigned long int c) { m_value = c; return *this; }
wxUniChar& operator=(short int c) { m_value = c; return *this; }
wxUniChar& operator=(unsigned short int c) { m_value = c; return *this; }
// Comparison operators:
// define the given comparison operator for all the types
#define wxDEFINE_UNICHAR_OPERATOR(op) \
bool operator op(const wxUniChar& c) const { return m_value op c.m_value; }\
bool operator op(char c) const { return m_value op From8bit(c); } \
bool operator op(unsigned char c) const { return m_value op From8bit((char)c); } \
wxIF_WCHAR_T_TYPE( bool operator op(wchar_t c) const { return m_value op (value_type)c; } ) \
bool operator op(int c) const { return m_value op (value_type)c; } \
bool operator op(unsigned int c) const { return m_value op (value_type)c; } \
bool operator op(short int c) const { return m_value op (value_type)c; } \
bool operator op(unsigned short int c) const { return m_value op (value_type)c; } \
bool operator op(long int c) const { return m_value op (value_type)c; } \
bool operator op(unsigned long int c) const { return m_value op (value_type)c; }
wxFOR_ALL_COMPARISONS(wxDEFINE_UNICHAR_OPERATOR)
#undef wxDEFINE_UNICHAR_OPERATOR
// this is needed for expressions like 'Z'-c
int operator-(const wxUniChar& c) const { return m_value - c.m_value; }
int operator-(char c) const { return m_value - From8bit(c); }
int operator-(unsigned char c) const { return m_value - From8bit((char)c); }
int operator-(wchar_t c) const { return m_value - (value_type)c; }
private:
// notice that we implement these functions inline for 7-bit ASCII
// characters purely for performance reasons
static value_type From8bit(char c)
{
if ( (unsigned char)c < 0x80 )
return c;
return FromHi8bit(c);
}
static char To8bit(value_type c)
{
if ( c < 0x80 )
return c;
return ToHi8bit(c);
}
// helpers of the functions above called to deal with non-ASCII chars
static value_type FromHi8bit(char c);
static char ToHi8bit(value_type c);
private:
value_type m_value;
};
// Writeable reference to a character in wxString.
//
// This class can be used in the same way wxChar is used, except that changing
// its value updates the underlying string object.
class WXDLLIMPEXP_BASE wxUniCharRef
{
private:
typedef wxStringImpl::iterator iterator;
// create the reference
#if wxUSE_UNICODE_UTF8
wxUniCharRef(wxStringIteratorNode& node, iterator pos) : m_node(node), m_pos(pos) {}
#else
wxUniCharRef(iterator pos) : m_pos(pos) {}
#endif
public:
// NB: we have to make this public, because we don't have wxString
// declaration available here and so can't declare wxString::iterator
// as friend; so at least don't use a ctor but a static function
// that must be used explicitly (this is more than using 'explicit'
// keyword on ctor!):
#if wxUSE_UNICODE_UTF8
static wxUniCharRef CreateForString(wxStringIteratorNode& node, iterator pos)
{ return wxUniCharRef(node, pos); }
#else
static wxUniCharRef CreateForString(iterator pos)
{ return wxUniCharRef(pos); }
#endif
wxUniChar::value_type GetValue() const { return UniChar().GetValue(); }
#if wxUSE_UNICODE_UTF8
wxUniChar::Utf8CharBuffer AsUTF8() const { return UniChar().AsUTF8(); }
#endif // wxUSE_UNICODE_UTF8
bool IsAscii() const { return UniChar().IsAscii(); }
// Assignment operators:
#if wxUSE_UNICODE_UTF8
wxUniCharRef& operator=(const wxUniChar& c);
#else
wxUniCharRef& operator=(const wxUniChar& c) { *m_pos = c; return *this; }
#endif
wxUniCharRef& operator=(const wxUniCharRef& c)
{ return *this = c.UniChar(); }
wxUniCharRef& operator=(char c) { return *this = wxUniChar(c); }
wxUniCharRef& operator=(unsigned char c) { return *this = wxUniChar(c); }
#if wxWCHAR_T_IS_REAL_TYPE
wxUniCharRef& operator=(wchar_t c) { return *this = wxUniChar(c); }
#endif
wxUniCharRef& operator=(int c) { return *this = wxUniChar(c); }
wxUniCharRef& operator=(unsigned int c) { return *this = wxUniChar(c); }
wxUniCharRef& operator=(short int c) { return *this = wxUniChar(c); }
wxUniCharRef& operator=(unsigned short int c) { return *this = wxUniChar(c); }
wxUniCharRef& operator=(long int c) { return *this = wxUniChar(c); }
wxUniCharRef& operator=(unsigned long int c) { return *this = wxUniChar(c); }
// Conversions to the same types as wxUniChar is convertible too:
operator char() const { return UniChar(); }
operator unsigned char() const { return UniChar(); }
#if wxWCHAR_T_IS_REAL_TYPE
operator wchar_t() const { return UniChar(); }
#endif
operator int() const { return UniChar(); }
operator unsigned int() const { return UniChar(); }
operator short int() const { return UniChar(); }
operator unsigned short int() const { return UniChar(); }
operator long int() const { return UniChar(); }
operator unsigned long int() const { return UniChar(); }
// see wxUniChar::operator bool etc. for explanation
operator bool() const { return (bool)UniChar(); }
bool operator!() const { return !UniChar(); }
bool operator&&(bool v) const { return UniChar() && v; }
// Comparison operators:
#define wxDEFINE_UNICHARREF_OPERATOR(op) \
bool operator op(const wxUniCharRef& c) const { return UniChar() op c.UniChar(); }\
bool operator op(const wxUniChar& c) const { return UniChar() op c; } \
bool operator op(char c) const { return UniChar() op c; } \
bool operator op(unsigned char c) const { return UniChar() op c; } \
wxIF_WCHAR_T_TYPE( bool operator op(wchar_t c) const { return UniChar() op c; } ) \
bool operator op(int c) const { return UniChar() op c; } \
bool operator op(unsigned int c) const { return UniChar() op c; } \
bool operator op(short int c) const { return UniChar() op c; } \
bool operator op(unsigned short int c) const { return UniChar() op c; } \
bool operator op(long int c) const { return UniChar() op c; } \
bool operator op(unsigned long int c) const { return UniChar() op c; }
wxFOR_ALL_COMPARISONS(wxDEFINE_UNICHARREF_OPERATOR)
#undef wxDEFINE_UNICHARREF_OPERATOR
// for expressions like c-'A':
int operator-(const wxUniCharRef& c) const { return UniChar() - c.UniChar(); }
int operator-(const wxUniChar& c) const { return UniChar() - c; }
int operator-(char c) const { return UniChar() - c; }
int operator-(unsigned char c) const { return UniChar() - c; }
int operator-(wchar_t c) const { return UniChar() - c; }
private:
#if wxUSE_UNICODE_UTF8
wxUniChar UniChar() const;
#else
wxUniChar UniChar() const { return *m_pos; }
#endif
friend class WXDLLIMPEXP_FWD_BASE wxUniChar;
private:
// reference to the string and pointer to the character in string
#if wxUSE_UNICODE_UTF8
wxStringIteratorNode& m_node;
#endif
iterator m_pos;
};
inline wxUniChar::wxUniChar(const wxUniCharRef& c)
{
m_value = c.UniChar().m_value;
}
inline wxUniChar& wxUniChar::operator=(const wxUniCharRef& c)
{
m_value = c.UniChar().m_value;
return *this;
}
// Comparison operators for the case when wxUniChar(Ref) is the second operand
// implemented in terms of member comparison functions
#define wxCMP_REVERSE(c1, c2, op) c2 op c1
wxDEFINE_COMPARISONS(char, const wxUniChar&, wxCMP_REVERSE)
wxDEFINE_COMPARISONS(char, const wxUniCharRef&, wxCMP_REVERSE)
wxDEFINE_COMPARISONS(wchar_t, const wxUniChar&, wxCMP_REVERSE)
wxDEFINE_COMPARISONS(wchar_t, const wxUniCharRef&, wxCMP_REVERSE)
wxDEFINE_COMPARISONS(const wxUniChar&, const wxUniCharRef&, wxCMP_REVERSE)
#undef wxCMP_REVERSE
// for expressions like c-'A':
inline int operator-(char c1, const wxUniCharRef& c2) { return -(c2 - c1); }
inline int operator-(const wxUniChar& c1, const wxUniCharRef& c2) { return -(c2 - c1); }
inline int operator-(wchar_t c1, const wxUniCharRef& c2) { return -(c2 - c1); }
#endif /* _WX_UNICHAR_H_ */