integer_digits.h File Reference

This file contains utilities for accessing digits of integers, and for converting them to strings. More...

#include <assert.h>
#include <algorithm>
#include <limits>
#include <type_traits>

Go to the source code of this file.

Classes
class	TwoDigitWriter
	Helper class for write_two_digits(), which creates a table that maps every integer from 0 to 99 to a two-char sequence that represents its two base 10 digits. More...
struct	DigitCounter< T, MinDigits, MaxDigits, typename >
	Functor that calculates the number of digits in an unsigned integer using binary search. More...
struct	DigitCounter< T, MinDigits, MaxDigits, typename std::enable_if< MinDigits==MaxDigits >::type >
	Counts the number of digits for the trivial case where the known minimum number of digits is equal to the known maximum number of digits. More...

Functions
char *	write_two_digits (int value, char *to)
	Writes an integer, which is between 0 (inclusive) and 100 (exclusive), to a string in base 10. More...
template<typename T >
constexpr int	count_digits (T x)
	Counts the number of base 10 digits in an unsigned integer. More...
template<typename T >
char *	write_digits (T number, int digits, char *to)
	Writes an unsigned integer of the specified length to a string. More...

Detailed Description

This file contains utilities for accessing digits of integers, and for converting them to strings.

Function Documentation

count_digits()

template<typename T >

constexpr int count_digits ( T  x )

constexpr

Counts the number of base 10 digits in an unsigned integer.

Parameters

x	the number whose digits to count

Returns

the number of digits in the number

write_digits()

template<typename T >

char * write_digits ( T  number, int  digits, char *  to  )

inline

Writes an unsigned integer of the specified length to a string.

The string is not zero-terminated.

Parameters

	number	the number to write
	digits	the number of digits to write (the number is zero-padded if it is shorter)
[in,out]	to	the destination string

Returns

pointer to the character just after the last digit

write_two_digits()

char * write_two_digits ( int  value, char *  to  )

inline

Writes an integer, which is between 0 (inclusive) and 100 (exclusive), to a string in base 10.

Always writes two digits, zero-padded if necessary. The string is not zero-terminated.

Parameters

	value	the number to write
[in,out]	to	the destination string

Returns

pointer to the character just after the last digit