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Unsigned Integer Number Generators (uint_, etc.)
Description

The uint_generator class is the simplest among the members of the numerics package. The uint_generator can generate unsigned integers of arbitrary length and size. The uint_generator generator can be used to generate ordinary primitive C/C++ integers or even user defined scalars such as bigints (unlimited precision integers) if the type follows certain expression requirements (for more information about the requirements, see below)). The uint_generator is a template class. Template parameters fine tune its behavior.

Header
// forwards to <boost/spirit/home/karma/numeric/uint.hpp>
#include <boost/spirit/include/karma_uint.hpp>

Also, see Include Structure.

Namespace

Name

boost::spirit::lit // alias: boost::spirit::karma::lit

boost::spirit::bin // alias: boost::spirit::karma::bin

boost::spirit::oct // alias: boost::spirit::karma::oct

boost::spirit::hex // alias: boost::spirit::karma::hex

boost::spirit::ushort_ // alias: boost::spirit::karma::ushort_

boost::spirit::ulong_ // alias: boost::spirit::karma::ulong_

boost::spirit::uint_ // alias: boost::spirit::karma::uint_

boost::spirit::ulong_long // alias: boost::spirit::karma::ulong_long

[Note] Note

The generators ulong_long and ulong_long(num) are only available on platforms where the preprocessor constant BOOST_HAS_LONG_LONG is defined (i.e. on platforms having native support for unsigned long long (64 bit) unsigned integer types).

[Note] Note

lit is reused by the String Generators, the Character Generators, and the Numeric Generators. In general, a char generator is created when you pass in a character, a string generator is created when you pass in a string, and a numeric generator is created when you use a numeric literal.

Synopsis
template <
    typename Num
  , unsigned Radix>
struct uint_generator;
Template parameters

Parameter

Description

Default

Num

The numeric base type of the numeric generator.

unsigned int

Radix

The radix base. This can be any value in the (inclusive) range from 2 .. 36.

10

Model of

PrimitiveGenerator

Notation

num

Numeric literal, any unsigned integer value, or a Lazy Argument that evaluates to an unsigned integer value of type Num

Num

Type of num: any unsigned integer type, or in case of a Lazy Argument, its return value

Radix

An integer literal specifying the required radix for the output conversion. Valid values are from the (inclusive) range 2 .. 36.

Expression Semantics

Semantics of an expression is defined only where it differs from, or is not defined in PrimitiveGenerator.

Expression

Semantics

lit(num)

Generate the unsigned integer literal num using the default formatting (radix is 10). This generator never fails (unless the underlying output stream reports an error).

ushort_
uint_
ulong_
ulong_long

Generate the unsigned integer provided by a mandatory attribute using the default formatting (radix is 10). This generator never fails (unless the underlying output stream reports an error).

ushort_(num)
uint_(num)
ulong_(num)
ulong_long(num)

Generate the unsigned integer provided by the immediate literal value the generator is initialized from using the default formatting (radix is 10). If this generator has an associated attribute it succeeds only if the attribute is equal to the immediate literal (unless the underlying output stream reports an error). Otherwise this generator fails and does not generate any output.

bin
oct
hex

Generate the unsigned integer provided by a mandatory attribute using the default formatting and the corresponding radix (bin: radix is 2, oct: radix is 8, hex: radix is 16). This generator never fails (unless the underlying output stream reports an error).

bin(num)
oct(num)
hex(num)

Generate the unsigned integer provided by the immediate literal value the generator is initialized from using the default formatting and the corresponding radix (bin: radix is 2, oct: radix is 8, hex: radix is 16). If this generator has an associated attribute it succeeds only if the attribute is equal to the immediate literal (unless the underlying output stream reports an error). Otherwise this generator fails and does not generate any output.

All generators listed in the table above (except lit(num)) are predefined specializations of the uint_generator<Num, Radix> basic unsigned integer number generator type described below. It is possible to directly use this type to create unsigned integer generators using a wide range of formatting options.

Expression

Semantics

uint_generator<
    Num, Radix
>()

Generate the unsigned integer of type Num provided by a mandatory attribute using the specified Radix (allowed values are from the (inclusive) range from 2 .. 36, the default value is 10).This generator never fails (unless the underlying output stream reports an error).

uint_generator<
    Num, Radix
>()(num)

Generate the unsigned integer of type Num provided by the immediate literal value the generator is initialized from, using the specified Radix (allowed values are from the (inclusive) range from 2 .. 36, the default value is 10). If this generator has an associated attribute it succeeds only if the attribute is equal to the immediate literal (unless the underlying output stream reports an error). Otherwise this generator fails and does not generate any output.

Additional Requirements

The following lists enumerate the requirements which must be met in order to use a certain type Num to instantiate and use a uint_generator<Num, Radix>.

If boost::is_integral<Num>::value is true the type Num must have defined:

If boost::is_integral<Num>::value is false the type Num must have defined:

Attributes

Expression

Attribute

lit(num)

unused

ushort_

unsigned short, attribute is mandatory (otherwise compilation will fail)

ushort_(num)

unsigned short, attribute is optional, if it is supplied, the generator compares the attribute with num and succeeds only if both are equal, failing otherwise.

uint_

unsigned int, attribute is mandatory (otherwise compilation will fail)

uint_(num)

unsigned int, attribute is optional, if it is supplied, the generator compares the attribute with num and succeeds only if both are equal, failing otherwise.

ulong_

unsigned long, attribute is mandatory (otherwise compilation will fail)

ulong_(num)

unsigned long, attribute is optional, if it is supplied, the generator compares the attribute with num and succeeds only if both are equal, failing otherwise.

ulong_long

unsigned long long, attribute is mandatory (otherwise compilation will fail)

ulong_long(num)

unsigned long long, attribute is optional, if it is supplied, the generator compares the attribute with num and succeeds only if both are equal, failing otherwise.

bin
oct
hex

unsigned int, attribute is mandatory (otherwise compilation will fail)

bin(num)
oct(num)
hex(num)

unsigned int, attribute is optional, if it is supplied, the generator compares the attribute with num and succeeds only if both are equal, failing otherwise.

uint_generator<
    Num, Radix
>()

Num, attribute is mandatory (otherwise compilation will fail)

uint_generator<
    Num, Radix
>()(num)

Num, attribute is optional, if it is supplied, the generator compares the attribute with num and succeeds only if both are equal, failing otherwise.

[Note] Note

In addition to their usual attribute of type Num all listed generators accept an instance of a boost::optional<Num> as well. If the boost::optional<> is initialized (holds a value) the generators behave as if their attribute was an instance of Num and emit the value stored in the boost::optional<>. Otherwise the generators will fail.

Complexity

O(N), where N is the number of digits needed to represent the generated integer number

Example
[Note] Note

The test harness for the example(s) below is presented in the Basics Examples section.

Some includes:

#include <boost/spirit/include/karma.hpp>
#include <boost/spirit/include/support_utree.hpp>
#include <boost/spirit/include/phoenix_core.hpp>
#include <boost/spirit/include/phoenix_operator.hpp>
#include <boost/fusion/include/std_pair.hpp>
#include <iostream>
#include <string>

Some using declarations:

using boost::spirit::karma::uint_;
using boost::spirit::karma::lit;

Basic usage of an uint generator:

test_generator("2", lit(2U));
test_generator("2", uint_(2));
test_generator_attr("2", uint_(2), 2);
test_generator_attr("", uint_(2), 3);    // fails (as 2 != 3)!
test_generator_attr("2", uint_, 2);


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