42 lines
837 B
C++
42 lines
837 B
C++
#pragma once
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#include <irrt/debug.hpp>
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#include <irrt/int_types.hpp>
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namespace
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{
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namespace range
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{
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template <typename T> T len(T start, T stop, T step)
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{
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// Reference:
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// https://github.com/python/cpython/blob/9dbd12375561a393eaec4b21ee4ac568a407cdb0/Objects/rangeobject.c#L933
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if (step > 0 && start < stop)
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return 1 + (stop - 1 - start) / step;
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else if (step < 0 && start > stop)
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return 1 + (start - 1 - stop) / (-step);
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else
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return 0;
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}
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} // namespace range
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/**
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* @brief A Python range.
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*/
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template <typename T> struct Range
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{
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T start;
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T stop;
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T step;
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/**
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* @brief Calculate the `len()` of this range.
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*/
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template <typename SizeT> T len()
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{
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debug_assert(SizeT, step != 0);
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return range::len(start, stop, step);
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}
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};
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} // namespace
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