c++ - Usage of auto for global constants -

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suppose have this:

namespace {   const unsigned my_uint = 100u;   const float my_float = 0.f;   const char* my_string = "hello world"; }

do expected behavior using auto these? presume improvement, i'm not sure in practice.

namespace {   auto my_uint = 100u;   auto my_float = 0.f;   auto my_string = "hello world"; }

are 2 code examples semantically same? these const automatically? if not, should specify auto const?

auto's deduction rules equivalent by-value template argument deduction. creating object value entails stripping references , top-level cv-qualifiers initializer. 2 examples not equivalent. in particular, primitive 100u of type unsigned int, that's deduced as. likewise, 0.f of type float.

adding const makes sense if variable itself not modified. if want make constants in program, using constexpr might better.


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