TUM/2015/ppc/common/include/util/CompileTimeConstraints.h

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2015-06-22 19:14:46 +02:00
/**
* \copyright
* (c) 2012 - 2015 E.S.R. Labs GmbH (http://www.esrlabs.com)
* All rights reserved.
*/
#ifndef COMPILETIMECONSTRAINTS_H_
#define COMPILETIMECONSTRAINTS_H_
#include "commonTypes.h"
#define ZGW_JOIN( X, Y ) ZGW_DO_JOIN( X, Y )
#define ZGW_DO_JOIN( X, Y ) ZGW_DO_JOIN2(X,Y)
#define ZGW_DO_JOIN2( X, Y ) X##Y
namespace common
{
template <bool x> struct STATIC_ASSERTION_FAILURE;
template <> struct STATIC_ASSERTION_FAILURE<true> { enum { value = 1 }; };
# define ECU_STATIC_ASSERT( B ) \
typedef char ZGW_JOIN(zgw_static_assert_typedef_, __LINE__) \
[ ::common::STATIC_ASSERTION_FAILURE< (bool)( B ) >::value ]
template<bool Condition>
struct CompileTimeError;
template<>
struct CompileTimeError<false> {};
/**
* STATIC_CHECK will fail when expr evaluates to true
*/
#define STATIC_CHECK(msg, expr) \
{ common::CompileTimeError<(expr)> ERROR_##msg; (void)ERROR_##msg; }
/**
* STATIC_ASSERT will fail when expr evaluates to false
* simple usage: STATIC_ASSERT(too_bad_static_assert_failed, 2 > 3)
*/
#define STATIC_ASSERT(msg, expr) \
{ common::CompileTimeError<!(expr)> ERROR_##msg; (void)ERROR_##msg; }
/**
* another example-setup for compile-time-check: a class only has to inherit from this constraint,
* so the constructor of this Constraint has to be compiled and the static check is executed
* by the compiler.
* will only compile if ACTUAL_SIZE <= ALLOWED_SIZE
*
* the argument passed to the STATIC_CHECK-macro can be any allowed C++-identifier,
*/
template<uint32 ACTUAL_SIZE, uint32 ALLOWED_SIZE>
struct ValidSizeConstraint
{
static void constraint()
{
STATIC_CHECK(fuck_allowed_size_is_too_small,
(ACTUAL_SIZE > ALLOWED_SIZE));
}
ValidSizeConstraint()
{
void (*p)() = constraint;
(*p)();//call function, only to make compiler warning about unused variable go away, will get optimized away
}
};
/**
* static checks
* usage:
* struct B {}; struct D : B { };
* ...Derived_from<D,B>();
*/
template<class T, class B> struct Derived_from
{
static void constraints(T* p) { B* pb = p; pb = pb;}
Derived_from() { void(*p)(T*) = constraints; p = p;}
};
template<class T1, class T2> struct Can_copy
{
static void constraints(T1 a, T2 b) { T2 c = a; b = a; c = a; b = a; }
Can_copy() { void(*p)(T1,T2) = constraints;}
};
template<class T1, class T2 = T1> struct Can_compare
{
static void constraints(T1 a, T2 b) { a==b; a!=b; a<b; }
Can_compare() { void(*p)(T1,T2) = constraints;}
};
}//namespace common
#endif /*COMPILETIMECONSTRAINTS_H_*/