Refactoring: remove implicit conversion from QCString to const char *

This commit changes the following in relation to string use
- The implicit convert from 'QCString' to 'const char *' is removed
- Strings parameters use 'const QCString &' as much as possible in favor
  over 'const char *'
- 'if (s)' where s is a QCString has been replaced by 'if(!s.isEmpty())'
- data() now always returns a valid C-string and not a 0-pointer.
- when passing a string 's' to printf and related functions 'qPrint(s)' is
  used instead of 's.data()'
- for empty string arguments 'QCString()' is used instead of '0'
- The copy() operation has been removed
- Where possible 'qstrcmp(a,b)==0' has been replaces by 'a==b' and
  'qstrcmp(a,b)<0' has been replaced by 'a<b'
- Parameters of string type that were default initialized with '= 0' are
  no initialized with '= QCString()'

1 files changed, 1 insertions, 1 deletions

diff --git a/src/dotlegendgraph.h b/src/dotlegendgraph.h
index 2d8eeec..2adf625 100644
--- a/src/dotlegendgraph.h
+++ b/src/dotlegendgraph.h
@@ -22,7 +22,7 @@
 class DotLegendGraph : public DotGraph
 {
   public:
-    void writeGraph(const char *path);
+    void writeGraph(const QCString &path);
 
   private:
     virtual QCString getBaseName() const;