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