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Parser Directive Ignoring Attribute (omit[])
Description

The omit[] ignores the attribute of its subject parser replacing it with unused.

Header
// forwards to <boost/spirit/home/qi/directive/omit.hpp>
#include <boost/spirit/include/qi_omit.hpp>

Also, see Include Structure.

Namespace

Name

boost::spirit::omit // alias: boost::spirit::qi::omit

Model of

UnaryParser

Notation

a

A Parser.

Expression Semantics

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

Expression

Semantics

omit[a]

Ignore the attribute of the subject parser, a

Attributes

Expression

Attribute

omit[a]

unused_type

Complexity

The complexity is defined by the complexity of the subject parser, a

Example
[Note] Note

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

Some using declarations:

using boost::spirit::qi::omit;
using boost::spirit::qi::int_;
using boost::spirit::ascii::char_;

This parser ignores the first two characters and extracts the succeeding int:

int i;
test_parser_attr("xx345", omit[char_ >> char_] >> int_, i);
std::cout << i << std::endl; // should print 345


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