cpp/locale/numpunct

The facet encapsulates numeric punctuation preferences. Stream I/O operations use through std and std for parsing numeric input and formatting numeric output.

The numbers that are supported by have the format described below. Here represents the radix set specified by the  argument value,  and  are the results of thousands_sep and decimal_point functions respectively. The format of integer values is as follows:

The number of digits between the s (maximum size of ) is specified by the result of grouping.

The format of floating-point values is as follows:

Specializations
The standard library is guaranteed to provide the following specializations (they are ):