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1. changed wxStringTokenizer to not modify the string we're iterating over

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but to just update our position in it (makes the code much more clear)
2. added GetLastDelimiter() to make up for lack of mode combining
   wxTOKEN_RET_EMPTY_ALL and RET_DELIMS
3. documented it and added unit tests for it


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@36552 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
This commit is contained in:
Vadim Zeitlin
2005-12-24 00:12:54 +00:00
parent 505a8c2ced
commit 4626c57c58
5 changed files with 112 additions and 62 deletions
Download Patch File Download Diff File Expand all files Collapse all files

105
src/common/tokenzr.cpp
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@@ -86,9 +86,7 @@ void wxStringTokenizer::Reinit(const wxString& str)
m_string = str;
m_pos = 0;
// empty string doesn't have any tokens
m_hasMore = !m_string.empty();
m_lastDelim = _T('\0');
}
// ----------------------------------------------------------------------------
@@ -100,49 +98,61 @@ bool wxStringTokenizer::HasMoreTokens() const
{
wxCHECK_MSG( IsOk(), false, _T("you should call SetString() first") );
if ( m_string.find_first_not_of(m_delims) == wxString::npos )
if ( m_string.find_first_not_of(m_delims, m_pos) != wxString::npos )
{
// no non empty tokens left, but in 2 cases we still may return true if
// GetNextToken() wasn't called yet for this empty token:
//
// a) in wxTOKEN_RET_EMPTY_ALL mode we always do it
// b) in wxTOKEN_RET_EMPTY mode we do it in the special case of a
// string containing only the delimiter: then there is an empty
// token just before it
return (m_mode == wxTOKEN_RET_EMPTY_ALL) ||
(m_mode == wxTOKEN_RET_EMPTY && m_pos == 0)
? m_hasMore : false;
}
else
{
// there are non delimiter characters left, hence we do have more
// tokens
// there are non delimiter characters left, so we do have more tokens
return true;
}
switch ( m_mode )
{
case wxTOKEN_RET_EMPTY:
case wxTOKEN_RET_DELIMS:
// special hack for wxTOKEN_RET_EMPTY: we should return the initial
// empty token even if there are only delimiters after it
return m_pos == 0 && !m_string.empty();
case wxTOKEN_RET_EMPTY_ALL:
// special hack for wxTOKEN_RET_EMPTY_ALL: we can know if we had
// already returned the trailing empty token after the last
// delimiter by examining m_lastDelim: it is set to NUL if we run
// up to the end of the string in GetNextToken(), but if it is not
// NUL yet we still have this last token to return even if m_pos is
// already at m_string.length()
return m_pos < m_string.length() || m_lastDelim != _T('\0');
case wxTOKEN_INVALID:
case wxTOKEN_DEFAULT:
wxFAIL_MSG( _T("unexpected tokenizer mode") );
// fall through
case wxTOKEN_STRTOK:
// never return empty delimiters
break;
}
return false;
}
// count the number of tokens in the string
// count the number of (remaining) tokens in the string
size_t wxStringTokenizer::CountTokens() const
{
wxCHECK_MSG( IsOk(), 0, _T("you should call SetString() first") );
// VZ: this function is IMHO not very useful, so it's probably not very
// important if it's implementation here is not as efficient as it
// could be - but OTOH like this we're sure to get the correct answer
// important if its implementation here is not as efficient as it
// could be -- but OTOH like this we're sure to get the correct answer
// in all modes
wxStringTokenizer *self = (wxStringTokenizer *)this; // const_cast
wxString stringInitial = m_string;
wxStringTokenizer tkz(m_string.c_str() + m_pos, m_delims, m_mode);
size_t count = 0;
while ( self->HasMoreTokens() )
while ( tkz.HasMoreTokens() )
{
count++;
(void)self->GetNextToken();
(void)tkz.GetNextToken();
}
self->Reinit(stringInitial);
return count;
}
@@ -152,9 +162,6 @@ size_t wxStringTokenizer::CountTokens() const
wxString wxStringTokenizer::GetNextToken()
{
// strtok() doesn't return empty tokens, all other modes do
bool allowEmpty = m_mode != wxTOKEN_STRTOK;
wxString token;
do
{
@@ -162,40 +169,40 @@ wxString wxStringTokenizer::GetNextToken()
{
break;
}
// find the end of this token
size_t pos = m_string.find_first_of(m_delims);
size_t pos = m_string.find_first_of(m_delims, m_pos);
// and the start of the next one
if ( pos == wxString::npos )
{
// no more delimiters, the token is everything till the end of
// string
token = m_string;
token.assign(m_string, m_pos, wxString::npos);
m_pos += m_string.length();
m_string.clear();
// skip the token
m_pos = m_string.length();
// no more tokens in this string, even in wxTOKEN_RET_EMPTY_ALL
// mode (we will return the trailing one right now in this case)
m_hasMore = false;
// it wasn't terminated
m_lastDelim = _T('\0');
}
else
else // we found a delimiter at pos
{
size_t pos2 = pos + 1;
// in wxTOKEN_RET_DELIMS mode we return the delimiter character
// with token
token = wxString(m_string, m_mode == wxTOKEN_RET_DELIMS ? pos2
: pos);
// with token, otherwise leave it out
size_t len = pos - m_pos;
if ( m_mode == wxTOKEN_RET_DELIMS )
len++;
// remove token with the following it delimiter from string
m_string.erase(0, pos2);
token.assign(m_string, m_pos, len);
// keep track of the position in the original string too
m_pos += pos2;
// skip the token and the trailing delimiter
m_pos = pos + 1;
m_lastDelim = m_string[pos];
}
}
while ( !allowEmpty && token.empty() );
while ( !AllowEmpty() && token.empty() );
return token;
}