Boost C++ Libraries

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switch_ Statement

#include <boost/phoenix/statement/switch.hpp>

The syntax is:

switch_(integral_expression)
[
    case_<integral_value>(sequenced_statements),
    ...
    default_<integral_value>(sequenced_statements)
]

A comma separated list of cases, and an optional default can be provided. Note unlike a normal switch statement, cases do not fall through.

Example: This code prints out "one", "two" or "other value" depending on the element's actual value:

std::for_each(c.begin(), c.end(),
    switch_(arg1)
    [
        case_<1>(std::cout << val("one") << '\n'),
        case_<2>(std::cout << val("two") << '\n'),
        default_(std::cout << val("other value") << '\n')
    ]
);

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