Shows C++ numeric limits for all possible numerical types, C++ (clang)

Shows C++ numeric limits for all possible numerical types

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//clang 3.8.0

/*************************************************************************
 * File:   numeric-limits.cpp 
 * Brief:  Shows the numeric limits for all possible numerical types.
 * Author: Caio Rodrigues
 *************************************************************************/

#include <iostream>
#include <limits>    // Numeric limits 
#include <iomanip>   // setw, and other IO manipulators 
#include <string>    // std::string 
#include <cstdint>   // uint8_t, int8_t, ...
#include <functional>

struct RowPrinter{
	int m_left;  // Left alignment 
	int m_right; // Right alignment  
	RowPrinter(int left, int right): m_left(left), m_right(right){
		// Print bool as 'true' or 'false' instead of 0 or 1.
		std::cout << std::boolalpha;
	}
	
	template<class A>
	auto printRow(const std::string& label, const A& value) const -> void {
		std::cout << std::setw(m_left)  << label
				  << std::setw(m_right) << value << "\n";
	}
};

#define SHOW_INTEGER_LIMITS(numtype) showNumericLimits<numtype>(#numtype)
#define SHOW_FLOAT_LIMITS(numtype)   showFloatPointLimits<numtype>(#numtype)

template <class T>
void showNumericLimits(const std::string& name){
	RowPrinter rp{30, 25};	
	std::cout << "Numeric limits for type: " << name << "\n";
	std::cout << std::string(60, '-') << "\n";
	rp.printRow("Type:",                    name);
	rp.printRow("Is integer:",              std::numeric_limits<T>::is_integer);
	rp.printRow("Is signed:",               std::numeric_limits<T>::is_signed);
	rp.printRow("Number of digits 10:",     std::numeric_limits<T>::digits10);
	rp.printRow("Max Number of digits 10:", std::numeric_limits<T>::max_digits10);

// RTTI - Run-Time Type Information 
	if(typeid(T) == typeid(uint8_t)
	   || typeid(T) == typeid(int8_t)
	   || typeid(T) == typeid(bool)
	   || typeid(T) == typeid(char)
	   || typeid(T) == typeid(unsigned char)
		){
		// Min Abs - samllest positive value for float point numbers 
		rp.printRow("Min Abs:",         static_cast<int>(std::numeric_limits<T>::min()));
		// Smallest value (can be negative)
		rp.printRow("Min:",             static_cast<int>(std::numeric_limits<T>::lowest()));
		// Largest value  
		rp.printRow("Max:",             static_cast<int>(std::numeric_limits<T>::max()));	
	} else {
		rp.printRow("Min Abs:",         std::numeric_limits<T>::min());
		rp.printRow("Min:",             std::numeric_limits<T>::lowest());
		rp.printRow("Max:",              std::numeric_limits<T>::max());
	}
	rp.printRow("Size in bytes:",       sizeof(T));
	rp.printRow("Size in bits:",        8 * sizeof(T));
	std::cout << "\n";
}

template<class T>
void showFloatPointLimits(const std::string& name){
	RowPrinter rp{30, 25};	
	showNumericLimits<T>(name);
	rp.printRow("Epsilon:",        std::numeric_limits<T>::epsilon());
	rp.printRow("Min exponent:",   std::numeric_limits<T>::min_exponent10);
	rp.printRow("Max exponent:",   std::numeric_limits<T>::max_exponent10);
}

int main(){
	SHOW_INTEGER_LIMITS(bool);
	SHOW_INTEGER_LIMITS(char);
	SHOW_INTEGER_LIMITS(unsigned char);
	SHOW_INTEGER_LIMITS(wchar_t);

// Standard integers in <cstdint>
	SHOW_INTEGER_LIMITS(int8_t);
	SHOW_INTEGER_LIMITS(uint8_t);
	SHOW_INTEGER_LIMITS(int16_t);
	SHOW_INTEGER_LIMITS(uint16_t);
	SHOW_INTEGER_LIMITS(int32_t);
	SHOW_INTEGER_LIMITS(uint32_t);
	SHOW_INTEGER_LIMITS(int64_t);
	SHOW_INTEGER_LIMITS(uint64_t);

SHOW_INTEGER_LIMITS(short);
	SHOW_INTEGER_LIMITS(unsigned short);
	SHOW_INTEGER_LIMITS(int);
	SHOW_INTEGER_LIMITS(unsigned int);
	SHOW_INTEGER_LIMITS(long);
	SHOW_INTEGER_LIMITS(unsigned long);
	SHOW_INTEGER_LIMITS(long long);
	SHOW_INTEGER_LIMITS(unsigned long long);
	
	SHOW_FLOAT_LIMITS(float);
	SHOW_FLOAT_LIMITS(double);
	SHOW_FLOAT_LIMITS(long double);
	
    return 0;
}

Show compiler warnings [ + ] Compiler args [ + ] Show input
Compilation time: 1.33 sec, absolute running time: 0.2 sec, cpu time: 0.14 sec, memory peak: 3 Mb, absolute service time: 1,54 sec

Numeric limits for type: bool ------------------------------------------------------------ Type: bool Is integer:true Is signed:false Number of digits 10: 0 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 1 Size in bytes: 1 Size in bits: 8 Numeric limits for type: char ------------------------------------------------------------ Type: char Is integer:true Is signed:true Number of digits 10: 2 Max Number of digits 10: 0 Min Abs: -128 Min: -128 Max: 127 Size in bytes: 1 Size in bits: 8 Numeric limits for type: unsigned char ------------------------------------------------------------ Type: unsigned char Is integer:true Is signed:false Number of digits 10: 2 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 255 Size in bytes: 1 Size in bits: 8 Numeric limits for type: wchar_t ------------------------------------------------------------ Type: wchar_t Is integer:true Is signed:true Number of digits 10: 9 Max Number of digits 10: 0 Min Abs: -2147483648 Min: -2147483648 Max: 2147483647 Size in bytes: 4 Size in bits: 32 Numeric limits for type: int8_t ------------------------------------------------------------ Type: int8_t Is integer:true Is signed:true Number of digits 10: 2 Max Number of digits 10: 0 Min Abs: -128 Min: -128 Max: 127 Size in bytes: 1 Size in bits: 8 Numeric limits for type: uint8_t ------------------------------------------------------------ Type: uint8_t Is integer:true Is signed:false Number of digits 10: 2 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 255 Size in bytes: 1 Size in bits: 8 Numeric limits for type: int16_t ------------------------------------------------------------ Type: int16_t Is integer:true Is signed:true Number of digits 10: 4 Max Number of digits 10: 0 Min Abs: -32768 Min: -32768 Max: 32767 Size in bytes: 2 Size in bits: 16 Numeric limits for type: uint16_t ------------------------------------------------------------ Type: uint16_t Is integer:true Is signed:false Number of digits 10: 4 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 65535 Size in bytes: 2 Size in bits: 16 Numeric limits for type: int32_t ------------------------------------------------------------ Type: int32_t Is integer:true Is signed:true Number of digits 10: 9 Max Number of digits 10: 0 Min Abs: -2147483648 Min: -2147483648 Max: 2147483647 Size in bytes: 4 Size in bits: 32 Numeric limits for type: uint32_t ------------------------------------------------------------ Type: uint32_t Is integer:true Is signed:false Number of digits 10: 9 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 4294967295 Size in bytes: 4 Size in bits: 32 Numeric limits for type: int64_t ------------------------------------------------------------ Type: int64_t Is integer:true Is signed:true Number of digits 10: 18 Max Number of digits 10: 0 Min Abs: -9223372036854775808 Min: -9223372036854775808 Max: 9223372036854775807 Size in bytes: 8 Size in bits: 64 Numeric limits for type: uint64_t ------------------------------------------------------------ Type: uint64_t Is integer:true Is signed:false Number of digits 10: 19 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 18446744073709551615 Size in bytes: 8 Size in bits: 64 Numeric limits for type: short ------------------------------------------------------------ Type: short Is integer:true Is signed:true Number of digits 10: 4 Max Number of digits 10: 0 Min Abs: -32768 Min: -32768 Max: 32767 Size in bytes: 2 Size in bits: 16 Numeric limits for type: unsigned short ------------------------------------------------------------ Type: unsigned short Is integer:true Is signed:false Number of digits 10: 4 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 65535 Size in bytes: 2 Size in bits: 16 Numeric limits for type: int ------------------------------------------------------------ Type: int Is integer:true Is signed:true Number of digits 10: 9 Max Number of digits 10: 0 Min Abs: -2147483648 Min: -2147483648 Max: 2147483647 Size in bytes: 4 Size in bits: 32 Numeric limits for type: unsigned int ------------------------------------------------------------ Type: unsigned int Is integer:true Is signed:false Number of digits 10: 9 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 4294967295 Size in bytes: 4 Size in bits: 32 Numeric limits for type: long ------------------------------------------------------------ Type: long Is integer:true Is signed:true Number of digits 10: 18 Max Number of digits 10: 0 Min Abs: -9223372036854775808 Min: -9223372036854775808 Max: 9223372036854775807 Size in bytes: 8 Size in bits: 64 Numeric limits for type: unsigned long ------------------------------------------------------------ Type: unsigned long Is integer:true Is signed:false Number of digits 10: 19 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 18446744073709551615 Size in bytes: 8 Size in bits: 64 Numeric limits for type: long long ------------------------------------------------------------ Type: long long Is integer:true Is signed:true Number of digits 10: 18 Max Number of digits 10: 0 Min Abs: -9223372036854775808 Min: -9223372036854775808 Max: 9223372036854775807 Size in bytes: 8 Size in bits: 64 Numeric limits for type: unsigned long long ------------------------------------------------------------ Type: unsigned long long Is integer:true Is signed:false Number of digits 10: 19 Max Number of digits 10: 0 Min Abs: 0 Min: 0 Max: 18446744073709551615 Size in bytes: 8 Size in bits: 64 Numeric limits for type: float ------------------------------------------------------------ Type: float Is integer:false Is signed:true Number of digits 10: 6 Max Number of digits 10: 9 Min Abs: 1.17549e-38 Min: -3.40282e+38 Max: 3.40282e+38 Size in bytes: 4 Size in bits: 32 Epsilon: 1.19209e-07 Min exponent: -37 Max exponent: 38 Numeric limits for type: double ------------------------------------------------------------ Type: double Is integer:false Is signed:true Number of digits 10: 15 Max Number of digits 10: 17 Min Abs: 2.22507e-308 Min: -1.79769e+308 Max: 1.79769e+308 Size in bytes: 8 Size in bits: 64 Epsilon: 2.22045e-16 Min exponent: -307 Max exponent: 308 Numeric limits for type: long double ------------------------------------------------------------ Type: long double Is integer:false Is signed:true Number of digits 10: 18 Max Number of digits 10: 21 Min Abs: 3.3621e-4932 Min: -1.18973e+4932 Max: 1.18973e+4932 Size in bytes: 16 Size in bits: 128 Epsilon: 1.0842e-19 Min exponent: -4931 Max exponent: 4932