io: add make_indented

io.hpp

@@ -59,6 +59,7 @@ namespace util {
     };
 
 
+    //-------------------------------------------------------------------------
     class indenter : public std::streambuf {
     protected:
         std::streambuf* m_dest;
@@ -76,7 +77,19 @@ namespace util {
         virtual ~indenter ();
     };
 
+    //-------------------------------------------------------------------------
+    template <typename T>
+    struct indented {
+        indented (const T &_data);
+        const T &data;
+    };
 
+
+    template <typename T>
+    indented<T>
+    make_indented (const T &_data);
+
+    //-------------------------------------------------------------------------
     class scoped_cwd {
         public:
             scoped_cwd ();
@@ -124,4 +137,11 @@ namespace util {
     };
 }
 
+
+template <typename T>
+std::ostream&
+operator<< (std::ostream &os, const util::indented<T> &v);
+
+#include "io.ipp"
+
 #endif

io.ipp

@@ -0,0 +1,29 @@
+
+#ifdef __UTIL_IO_IPP
+#error "multiple inclusions"
+#else
+#define __UTIL__IO_IPP
+#endif
+
+namespace util {
+    template <typename T>
+    indented<T>::indented (const T &_data):
+        data (_data)
+    { ; }
+
+
+    template <typename T>
+    indented<T>
+    make_indented (const T &_data) {
+        return indented<T> (_data);
+    }
+}
+
+
+template <typename T>
+std::ostream&
+operator<< (std::ostream &os, const util::indented<T> &v) {
+    util::indenter raii (os);
+    os << v.data;
+    return os;
+}