Revert part of 47973dc2b, which was causing bug #11873.

diff --git a/src/graphics/PreviewLoader.cpp b/src/graphics/PreviewLoader.cpp
index f15752cc11f45338320edb988e6dfbc3565cf7c9..e3daaa770415d24a563f650cc3fd2819b8b3ec24 100644 (file)
--- a/src/graphics/PreviewLoader.cpp
+++ b/src/graphics/PreviewLoader.cpp
@@ -319,18 +319,26 @@ Buffer const & PreviewLoader::buffer() const
 
 namespace {
 
-std::function<SnippetPair (string const &)> IncrementedFileName
-       (string const & to_format, string const & filename_base)
-{
-       return [&to_format, &filename_base](string const & snippet)
+class IncrementedFileName {
+public:
+       IncrementedFileName(string const & to_format,
+                           string const & filename_base)
+               : to_format_(to_format), base_(filename_base), counter_(1)
+       {}
+
+       SnippetPair const operator()(string const & snippet)
        {
-               static int counter_ = 1;
                ostringstream os;
-               os << filename_base << counter_++ << '.' << to_format;
-               string const file = os.str();
-               return make_pair(snippet, FileName(file));
-       };
-}
+               os << base_ << counter_++ << '.' << to_format_;
+               string const file_name = os.str();
+               return make_pair(snippet, FileName(file_name));
+       }
+       
+private:
+       string const & to_format_;
+       string const & base_;
+       int counter_;
+};
 
 
 InProgress::InProgress(string const & filename_base,