C++ Language/Templates/TemplateParameters/DeducingTemplateParameters
Traditionally, template object initialization needed to explicitly list types: std::pair<float,int> fiVar = std::pair<float,int>(1.1F,2);
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Modern C++ compilers can automatically deduce those types: std::pair fiVar = std::pair(1.1F,2);
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Additional information about deducing template-parameters (includes interactive examples)