arg_router::multi_lang::root_wrapper_t< Fn, SupportedISOLanguageCodes > Class Template Reference

#include <arg_router/multi_lang/root_wrapper.hpp>

Public Member Functions
	root_wrapper_t (std::string_view iso_language, Fn &&f)
void	parse (int argc, char **argv) const
void	help (std::ostream &stream) const
string	help () const

Detailed Description

template<typename Fn, typename... SupportedISOLanguageCodes>
class arg_router::multi_lang::root_wrapper_t< Fn, SupportedISOLanguageCodes >

A wrapper around a root node that provides multi-language support.

The wrapper relies on the use of string_selector (or SM_) to provide compile-time selection of language variants for strings. The wrapper simply creates a root variant for the given ISO language code. If the given ISO language code does not match any of the supporting ones, then the first supported language is used as a fallback.

namespace ar = arg_router;
namespace arp = ar::policy;
 
ar::multi_lang::root_wrapper<S_("en_GB"), S_("fr"), S_("es")>{
    ar::multi_lang::iso_locale(std::locale("").name()),
    [&](auto I) {
        return ar::root(my_validator{},
            ar::help(arp::long_name<SM_(I, "help", "aider", "ayuda")>,
                     arp::short_name<'h'>,
                     arp::program_name<S_("is_even")>,
                     arp::program_version<S_(version)>,
                     arp::program_addendum<SM_(I, "An example program for arg_router.",
                                                  "Un exemple de programme pour arg_router.",
                                                  "Un programa de ejemplo para arg_router")>,
            ...

As implied by the above example, the supported language is given by index to the function object that returns the root instance. This means that each use of string_selector must have the same number of language options, in the same order. The latter requirement is especially important as this cannot be checked by arg_router.

Fn is a function object used to return a given root type from a supported language index, its signature must match:

template <typename IntegralConstant>
auto operator()(IntegralConstant I) {
    ...
};

The SupportedISOLanguageCodes parameters can be any set of unique strings, but as they are compared against an input that would usually come from a std::locale() call, then ISO language codes are least troublesome and easiest to read.

Note

This has now been superceded by multi_lang::root_t, and will be removed in v2

Template Parameters

Fn	Function object type that accepts an integral constant (the supported language index) and returns a root instance
SupportedISOLanguageCodes	The supported ISO language codes as compile time strings

Definition at line 67 of file root_wrapper.hpp.

Constructor & Destructor Documentation

root_wrapper_t()

template<typename Fn , typename... SupportedISOLanguageCodes>

arg_router::multi_lang::root_wrapper_t< Fn, SupportedISOLanguageCodes >::root_wrapper_t ( std::string_view  iso_language, Fn &&  f  )

inlineexplicit

Constructor

Parameters

iso_language	The runtime language selection, if it doesn't match any of SupportedISOLanguageCodes, then the first language in SupportedISOLanguageCodes is used
f	Function object that returns the root instance for a given supported language index

Definition at line 92 of file root_wrapper.hpp.

Member Function Documentation

help() [1/2]

template<typename Fn , typename... SupportedISOLanguageCodes>

string arg_router::multi_lang::root_wrapper_t< Fn, SupportedISOLanguageCodes >::help ( ) const

inline

Calls the help method on the selected root.

Returns

String holding the help output

Definition at line 132 of file root_wrapper.hpp.

help() [2/2]

template<typename Fn , typename... SupportedISOLanguageCodes>

void arg_router::multi_lang::root_wrapper_t< Fn, SupportedISOLanguageCodes >::help ( std::ostream &  stream ) const

inline

Calls the help method on the selected root.

Parameters

stream

Output stream to write into

Definition at line 123 of file root_wrapper.hpp.

parse()

template<typename Fn , typename... SupportedISOLanguageCodes>

void arg_router::multi_lang::root_wrapper_t< Fn, SupportedISOLanguageCodes >::parse ( int  argc, char **  argv  ) const

inline

Calls the parse method on the selected root.

Parameters

argc	Number of arguments
argv	Array of char pointers to the command line tokens

Definition at line 114 of file root_wrapper.hpp.

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The documentation for this class was generated from the following file:

• arg_router/multi_lang/root_wrapper.hpp