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34 lines
1 KiB
C++
34 lines
1 KiB
C++
#pragma once
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///@file
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/**
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* Awful hacky generation of the comparison operators by doing a lexicographic
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* comparison between the choosen fields.
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*
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* ```
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* GENERATE_CMP(ClassName, me->field1, me->field2, ...)
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* ```
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*
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* will generate comparison operators semantically equivalent to:
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*
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* ```
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* bool operator<(const ClassName& other) {
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* return field1 < other.field1 && field2 < other.field2 && ...;
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* }
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* ```
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*/
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#define GENERATE_ONE_CMP(COMPARATOR, MY_TYPE, ...) \
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bool operator COMPARATOR(const MY_TYPE& other) const { \
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__VA_OPT__(const MY_TYPE* me = this;) \
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auto fields1 = std::make_tuple( __VA_ARGS__ ); \
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__VA_OPT__(me = &other;) \
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auto fields2 = std::make_tuple( __VA_ARGS__ ); \
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return fields1 COMPARATOR fields2; \
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}
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#define GENERATE_EQUAL(args...) GENERATE_ONE_CMP(==, args)
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#define GENERATE_LEQ(args...) GENERATE_ONE_CMP(<, args)
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#define GENERATE_NEQ(args...) GENERATE_ONE_CMP(!=, args)
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#define GENERATE_CMP(args...) \
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GENERATE_EQUAL(args) \
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GENERATE_LEQ(args) \
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GENERATE_NEQ(args)
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