Boost C++ Libraries

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This is the documentation for a snapshot of the master branch, built from commit 80e75653fc.
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grammar::tuple_rule

Match a series of rules in order.

Synopsis

Defined in header <boost/url/grammar/tuple_rule.hpp>

template<
    class... Rules>
constexpr implementation-defined
tuple_rule(
    Rules... rn);
Description

This matches a series of rules in the order specified. Upon success the input will be adjusted to point to the first unconsumed character. There is no implicit specification of linear white space between each rule.

Value Type
using value_type = see-below;

The sequence rule usually returns a std::tuple containing the the value_type of each corresponding rule in the sequence, except that void values are removed. However, if there is exactly one non-void value type T, then the sequence rule returns result<T> instead of result<tuple<...>>.

Example

Rules are used with the function parse.

result< std::tuple< unsigned char, unsigned char, unsigned char, unsigned char > > rv =
    parse( "192.168.0.1",
        tuple_rule(
            dec_octet_rule,
            squelch( delim_rule('.') ),
            dec_octet_rule,
            squelch( delim_rule('.') ),
            dec_octet_rule,
            squelch( delim_rule('.') ),
            dec_octet_rule ) );
BNF
sequence     = rule1 rule2 rule3...
Specification
Parameters

Name

Description

rn

A list of one or more rules to match

See Also

dec_octet_rule, delim_rule, parse, squelch.

Convenience header <boost/url/grammar.hpp>


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