Index: options_description.cpp
===================================================================
RCS file: /cvsroot/boost/boost/libs/program_options/src/options_description.cpp,v
retrieving revision 1.14
retrieving revision 1.15
diff -u -p -r1.14 -r1.15
--- options_description.cpp	13 Jul 2005 16:32:40 -0000	1.14
+++ options_description.cpp	22 Dec 2005 09:29:14 -0000	1.15
@@ -291,11 +291,26 @@ namespace boost { namespace program_opti
 
     namespace {
 
+        /* Given a string 'par', that contains no newline characters
+           outputs it to 'os' with wordwrapping, that is, as several
+           line.
+
+           Each output line starts with 'indent' space characters, 
+           following by characters from 'par'. The total length of
+           line is no longer than 'line_length'.
+                                      
+        */
         void format_paragraph(std::ostream& os,
                               std::string par,
-                              unsigned first_column_width,
+                              unsigned indent,
                               unsigned line_length)
         {                    
+            // Through reminder of this function, 'line_length' will
+            // be the length available for characters, not including
+            // indent.
+            assert(indent < line_length);
+            line_length -= indent;
+
             // index of tab (if present) is used as additional indent relative
             // to first_column_width if paragrapth is spanned over multiple
             // lines if tab is not on first line it is ignored
@@ -319,16 +334,16 @@ namespace boost { namespace program_opti
 
                 // this assert may fail due to user error or 
                 // environment conditions!
-                assert(par_indent < (line_length - first_column_width));
+                assert(par_indent < line_length);
 
                 // ignore tab if not on first line
-                if (par_indent >= (line_length - first_column_width))
+                if (par_indent >= line_length)
                 {
                     par_indent = 0;
                 }            
             }
           
-            if (par.size() < (line_length - first_column_width))
+            if (par.size() < line_length)
             {
                 os << par;
             }
@@ -337,17 +352,16 @@ namespace boost { namespace program_opti
                 string::const_iterator       line_begin = par.begin();
                 const string::const_iterator par_end = par.end();
 
-                bool first_line = true; // of current paragraph!
-            
-                unsigned indent = first_column_width;
+                bool first_line = true; // of current paragraph!        
             
                 while (line_begin < par_end)  // paragraph lines
                 {
                     if (!first_line)
                     {
-                        // trimm leading single spaces
-                        // if (firstchar == ' ') &&
-                        //    ((exists(firstchar + 1) && (firstchar + 1 != ' '))
+                        // If line starts with space, but second character
+                        // is not space, remove the leading space.
+                        // We don't remove double spaces because those
+                        // might be intentianal.
                         if ((*line_begin == ' ') &&
                             ((line_begin + 1 < par_end) &&
                              (*(line_begin + 1) != ' ')))
@@ -357,30 +371,26 @@ namespace boost { namespace program_opti
                     }
 
                     string::const_iterator line_end;
-                
-                    if (line_begin + (line_length - indent) > par_end)
+
+                    line_end = line_begin + line_length;
+                    if (line_end > par_end)
                     {
                         line_end = par_end;
                     }
-                    else
-                    {
-                        line_end = line_begin + (line_length - indent);
-                    }
             
                     // prevent chopped words
-                    // if (lastchar != ' ') &&
-                    //    ((exists(lastchar + 1) && (lastchar + 1 != ' '))
+                    // Is line_end between two non-space characters?
                     if ((*(line_end - 1) != ' ') &&
                         ((line_end < par_end) && (*line_end != ' ')))
                     {
                         // find last ' ' in the second half of the current paragraph line
                         string::const_iterator last_space =
-                            find(reverse_iterator<string::const_iterator>(line_end - 1),
-                                 reverse_iterator<string::const_iterator>(line_begin - 1),
+                            find(reverse_iterator<string::const_iterator>(line_end),
+                                 reverse_iterator<string::const_iterator>(line_begin),
                                  ' ')
                             .base();
                 
-                        if (last_space != line_begin - 1)
+                        if (last_space != line_begin)
                         {                 
                             // is last_space within the second half ot the 
                             // current line
@@ -397,7 +407,7 @@ namespace boost { namespace program_opti
               
                     if (first_line)
                     {
-                        indent = first_column_width + par_indent;
+                        indent += par_indent;
                         first_line = false;
                     }
 
@@ -436,7 +446,7 @@ namespace boost { namespace program_opti
             assert(line_length > first_column_width);
 
             // Note: can't use 'tokenizer' as name of typedef -- borland
-            // will consider subsequence uses of 'tokenizer' as uses of
+            // will consider uses of 'tokenizer' below as uses of
             // boost::tokenizer, not typedef.
             typedef boost::tokenizer<boost::char_separator<char> > tok;