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diff --git a/library/cpp/yt/misc/preprocessor.h b/library/cpp/yt/misc/preprocessor.h
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+#pragma once
+
+/*!
+ * \file preprocesor.h
+ * \brief Preprocessor metaprogramming macroses
+ */
+
+#if !defined(_MSC_VER) && !defined(__GNUC__)
+#   error Your compiler is not currently supported.
+#endif
+
+/*!
+ * \defgroup yt_pp Preprocessor metaprogramming macroses
+ * \ingroup yt_commons
+ *
+ * This is collection of macro definitions for various metaprogramming tasks
+ * with the preprocessor.
+ *
+ * \{
+ *
+ * \page yt_pp_sequences Sequences
+ * Everything revolves around the concept of a \em sequence. A typical
+ * sequence is encoded like <tt>(1)(2)(3)...</tt>. Internally this allows
+ * to apply some macro to the every element in the sequence (see #PP_FOR_EACH).
+ *
+ * Note that sequences can be nested, i. e. <tt>((1)(2)(3))(a)(b)(c)</tt>
+ *
+ * \page yt_pp_examples Examples
+ * Please refer to the unit test for an actual example of usage
+ * (unittests/preprocessor_ut.cpp).
+ *
+ */
+
+//! Concatenates two tokens.
+#define PP_CONCAT(x, y)   PP_CONCAT_A(x, y)
+//! \cond Implementation
+#define PP_CONCAT_A(x, y) PP_CONCAT_B(x, y)
+#define PP_CONCAT_B(x, y) x ## y
+//! \endcond
+
+//! Transforms token into the string forcing argument expansion.
+#define PP_STRINGIZE(x)   PP_STRINGIZE_A(x)
+//! \cond Implementation
+#define PP_STRINGIZE_A(x) PP_STRINGIZE_B(x)
+#define PP_STRINGIZE_B(x) #x
+//! \endcond
+
+//! \cond Implementation
+#define PP_LEFT_PARENTHESIS (
+#define PP_RIGHT_PARENTHESIS )
+#define PP_COMMA() ,
+#define PP_EMPTY()
+//! \endcond
+
+//! Performs (non-lazy) conditional expansion.
+/*!
+ * \param cond Condition; should expands to either \c PP_TRUE or \c PP_FALSE.
+ * \param _then Expansion result in case when \c cond holds.
+ * \param _else Expansion result in case when \c cond does not hold.
+ */
+#define PP_IF(cond, _then, _else) PP_CONCAT(PP_IF_, cond)(_then, _else)
+//! \cond Implementation
+#define PP_IF_PP_TRUE(x, y) x
+#define PP_IF_PP_FALSE(x, y) y
+//! \endcond
+
+//! Tests whether supplied argument can be treated as a sequence
+//! (i. e. <tt>()()()...</tt>)
+#define PP_IS_SEQUENCE(arg) PP_CONCAT(PP_IS_SEQUENCE_B_, PP_COUNT((PP_NIL PP_IS_SEQUENCE_A arg PP_NIL)))
+//! \cond Implementation
+#define PP_IS_SEQUENCE_A(_) PP_RIGHT_PARENTHESIS PP_LEFT_PARENTHESIS
+#define PP_IS_SEQUENCE_B_1 PP_FALSE
+#define PP_IS_SEQUENCE_B_2 PP_TRUE
+//! \endcond
+
+//! Computes the number of elements in the sequence.
+#define PP_COUNT(...) PP_COUNT_IMPL(__VA_ARGS__)
+
+//! Removes first \c n elements from the sequence.
+#define PP_KILL(seq, n) PP_KILL_IMPL(seq, n)
+
+//! Extracts the head of the sequence.
+/*! For example, \code PP_HEAD((0)(1)(2)(3)) == 0 \endcode
+ */
+#define PP_HEAD(...) PP_HEAD_IMPL(__VA_ARGS__)
+
+//! Extracts the tail of the sequence.
+/*! For example, \code PP_TAIL((0)(1)(2)(3)) == (1)(2)(3) \endcode
+ */
+#define PP_TAIL(...) PP_TAIL_IMPL(__VA_ARGS__)
+
+//! Extracts the element with the specified index from the sequence.
+/*! For example, \code PP_ELEMENT((0)(1)(2)(3), 1) == 1 \endcode
+ */
+#define PP_ELEMENT(seq, index) PP_ELEMENT_IMPL(seq, index)
+
+//! Applies the macro to every member of the sequence.
+/*! For example,
+ * \code
+ * #define MyFunctor(x) +x+
+ * PP_FOR_EACH(MyFunctor, (0)(1)(2)(3)) == +0+ +1+ +2+ +3+
+ * \encode
+ */
+#define PP_FOR_EACH(what, seq) PP_FOR_EACH_IMPL(what, seq)
+
+//! Declares an anonymous variable.
+#ifdef __COUNTER__
+#define PP_ANONYMOUS_VARIABLE(str) PP_CONCAT(str, __COUNTER__)
+#else
+#define PP_ANONYMOUS_VARIABLE(str) PP_CONCAT(str, __LINE__)
+#endif
+
+//! Insert prefix based on presence of additional arguments.
+#define PP_ONE_OR_NONE(a, ...) PP_THIRD(a, ## __VA_ARGS__, a)
+#define PP_THIRD(a, b, ...) __VA_ARGS__
+
+//! \cond Implementation
+#define PREPROCESSOR_GEN_H_
+#include "preprocessor-gen.h"
+#undef PREPROCESSOR_GEN_H_
+//! \endcond
+
+/*! \} */
+