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## Macro BOOST_LOCAL_FUNCTION_NAME

BOOST_LOCAL_FUNCTION_NAME — This macro is used to end a local function declaration specifying its name.

## Synopsis

    // In header: <boost/local_function.hpp>

    BOOST_LOCAL_FUNCTION_NAME(qualified_name)

## Description

This macro must follow the local function body code block `{ ... }`:

    { // Some declarative context.
        ...
        result_type BOOST_LOCAL_FUNCTION(declarations) {
            ... // Body code.
        } BOOST_LOCAL_FUNCTION_NAME(qualified_name)
        ...
    }

Within templates, the special macros `BOOST_LOCAL_FUNCTION_TPL` and `BOOST_LOCAL_FUNCTION_NAME_TPL` must be used.

Parameters:

`qualified_name`

The name of the local function optionally qualified as follow:

    name:
            [inline] [recursive] local_function_name

(Lexical conventions: `token1 | token2` means either `token1` or `token2`; `[token]` means either `token` or nothing; `{expression}` means the token resulting from the expression.)

The local function name can be qualified by prefixing it with the keyword `inline` (see the Advanced Topics section):

    BOOST_LOCAL_FUNCTION_NAME(inline local_function_name)

This increases the chances that the compiler will be able to inline the local function calls (thus reducing run-time). However, inline local functions cannot be passed as template parameters (e.g., to `std::for_each`) or assigned to other functors (e.g., to `boost::function`). That is true on C++03 compilers but inline local functions can instead be passed as template parameters on C++11 compilers. On C++11 compilers, there is no need to declare a local function lined because this library will automatically use C++11 specific features to inline the local function while always allowing to pass it as a template parameter. This optimization is automatically enabled when the Boost.Config macro `BOOST_NO_CXX11_LOCAL_CLASS_TEMPLATE_PARAMETERS` is not defined but it also be forced using `BOOST_LOCAL_FUNCTION_CONFIG_LOCALS_AS_TPARAMS`.

The local function name can also be qualified by prefixing it with the "keyword" `recursive` (see the Advanced Topics section):

    BOOST_LOCAL_FUNCTION_NAME(recursive local_function_name)

This allows the local function to recursively call itself from its body (as usual in C++). However, recursive local functions should only be called within their declaration scope (otherwise the result is undefined behaviour). Finally, compilers have not been observed to be able to inline recursive local function calls, not even when the recursive local function is also declared inline:

    BOOST_LOCAL_FUNCTION(inline recursive local_function_name)

Note: The local function name cannot be the name of an operator `operator...` and it cannot be the same name of another local function declared within the same enclosing scope (but `boost::overloaded_function` can be used to overload local functions, see Boost.Functional/OverloadedFunction and the Advanced Topics section).

See: Tutorial section, Advanced Topics section, `BOOST_LOCAL_FUNCTION`, `BOOST_LOCAL_FUNCTION_NAME_TPL`.