Adding upstream version 1.44.3.upstream/1.44.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/ml/dlib/dlib/metaprogramming.h b/ml/dlib/dlib/metaprogramming.h
new file mode 100644
index 000000000..bc63041ff
--- /dev/null
+++ b/ml/dlib/dlib/metaprogramming.h
@@ -0,0 +1,71 @@
+// Copyright (C) 2017  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+#ifndef DLIB_METApROGRAMMING_Hh_
+#define DLIB_METApROGRAMMING_Hh_
+
+
+namespace dlib
+{
+
+// ----------------------------------------------------------------------------------------
+
+    template <size_t... n>
+    struct compile_time_integer_list 
+    {
+        /*!
+            WHAT THIS OBJECT REPRESENTS
+                The point of this type is to, as the name suggests, hold a compile time list of integers.
+                As an example, here is something simple you could do with it:
+
+                    template <size_t... ints>
+                    void print_compile_time_ints (
+                        compile_time_integer_list<ints...>
+                    )
+                    {
+                        print(ints...);
+                    }
+
+                    int main()
+                    {
+                        print_compile_time_ints(compile_time_integer_list<0,4,9>());
+                    }
+
+                Which just calls: print(0,4,9);
+
+                This is a simple example, but this kind of thing is useful in larger and
+                more complex template metaprogramming constructs.
+        !*/
+
+        template <size_t m>
+        struct push_back
+        {
+            typedef compile_time_integer_list<n..., m> type;
+        };
+    };
+
+// ----------------------------------------------------------------------------------------
+
+    template <size_t max>
+    struct make_compile_time_integer_range
+    {
+        /*!
+            WHAT THIS OBJECT REPRESENTS
+                This object makes a compile_time_integer_list containing the integers in the range [1,max] inclusive.
+                For example:
+                    make_compile_time_integer_range<4>::type
+                evaluates to:
+                    compile_time_integer_list<1,2,3,4>
+        !*/
+
+        typedef typename make_compile_time_integer_range<max-1>::type::template push_back<max>::type type;
+    };
+    // base case
+    template <> struct make_compile_time_integer_range<0> { typedef compile_time_integer_list<> type; };
+
+// ----------------------------------------------------------------------------------------
+
+}
+
+#endif // DLIB_METApROGRAMMING_Hh_
+
+