Options::Parser< OptionList, Group > Class Template Reference

Class that handles parsing an input file. More...

#include <ParseOptions.hpp>

Public Member Functions
	Parser (std::string help_text) noexcept
void	parse (std::string options) noexcept
	Parse a string to obtain options and their values. More...
void	parse (const Option &options)
	Parse an Option to obtain options and their values.
void	parse_file (const std::string &file_name) noexcept
	Parse a file containing options. More...
template<typename T , typename Metavariables = NoSuchType>
T::type	get () const
	Get the value of the specified option. More...
template<typename TagList , typename Metavariables = NoSuchType, typename F >
decltype(auto)	apply (F &&func) const
	Call a function with the specified options as arguments. More...
template<typename Metavariables = NoSuchType, typename F >
decltype(auto)	apply_all (F &&func) const
	Call a function with the typelist of parsed options (i.e., the supplied option list with the chosen branches of any Alternatives inlined) and the option values as arguments. More...
template<typename TagsAndSubgroups = tags_and_subgroups_list>
std::string	help () const noexcept
	Get the help string.
void	pup (PUP::er &p) noexcept
template<typename Tag , typename Metavariables >
Tag::type	get () const
template<typename OverlayOptions >
void	overlay (std::string options) noexcept
	Overlay the options from a string or file on top of the currently parsed options. More...
template<typename OverlayOptions >
void	overlay_file (const std::string &file_name) noexcept
	Overlay the options from a string or file on top of the currently parsed options. More...

Detailed Description

template<typename OptionList, typename Group = NoSuchType>
class Options::Parser< OptionList, Group >

Class that handles parsing an input file.

Options must be given YAML data to parse before output can be extracted. This can be done either from a file (parse_file method), from a string (parse method), or, in the case of recursive parsing, from an Option (parse method). The options can then be extracted using the get method.

Example

struct Bounded {
  using type = int;
  static constexpr Options::String help = {
      "Option with bounds and a suggested value"};
  // These are optional
  static type suggested_value() noexcept { return 3; }
  static type lower_bound() noexcept { return 2; }
  static type upper_bound() noexcept { return 10; }
};

  Options::Parser<tmpl::list<Bounded>> opts("Overall help text");
  opts.parse("Bounded: 3");
  CHECK(opts.get<Bounded>() == 3);

See also

the Option Parsing tutorial

Template Parameters

OptionList	the list of option structs to parse
Group	the option group with a group hierarchy

Constructor & Destructor Documentation

Parser()

template<typename OptionList , typename Group >

Options::Parser< OptionList, Group >::Parser ( std::string  help_text )

explicitnoexcept

Parameters

help_text

an overall description of the options

Member Function Documentation

apply()

template<typename OptionList , typename Group = NoSuchType>

template<typename TagList , typename Metavariables = NoSuchType, typename F >

decltype(auto) Options::Parser< OptionList, Group >::apply

(

F &&

func

)

const

Call a function with the specified options as arguments.

Template Parameters

TagList

a typelist of options to pass

Returns: the result of the function call

apply_all()

template<typename OptionList , typename Group = NoSuchType>

template<typename Metavariables = NoSuchType, typename F >

decltype(auto) Options::Parser< OptionList, Group >::apply_all

(

F &&

func

)

const

Call a function with the typelist of parsed options (i.e., the supplied option list with the chosen branches of any Alternatives inlined) and the option values as arguments.

Returns: the result of the function call. This must have the same type for all valid sets of parsed arguments.

get()

template<typename OptionList , typename Group = NoSuchType>

template<typename T , typename Metavariables = NoSuchType>

T::type Options::Parser< OptionList, Group >::get

(

)

const

Get the value of the specified option.

Template Parameters

T	the option to retrieve

Returns: the value of the option

overlay()

template<typename OptionList , typename Group >

template<typename OverlayOptions >

void Options::Parser< OptionList, Group >::overlay ( std::string  options )

noexcept

Overlay the options from a string or file on top of the currently parsed options.

Any tag included in the list passed as the template parameter can be overridden by a new parsed value. Newly parsed options replace the previous values. Any tags not appearing in the new input are left unchanged.

overlay_file()

template<typename OptionList , typename Group >

template<typename OverlayOptions >

void Options::Parser< OptionList, Group >::overlay_file ( const std::string &  file_name )

noexcept

Overlay the options from a string or file on top of the currently parsed options.

Any tag included in the list passed as the template parameter can be overridden by a new parsed value. Newly parsed options replace the previous values. Any tags not appearing in the new input are left unchanged.

parse()

template<typename OptionList , typename Group >

void Options::Parser< OptionList, Group >::parse ( std::string  options )

noexcept

Parse a string to obtain options and their values.

Parameters

options

the string holding the YAML formatted options

parse_file()

template<typename OptionList , typename Group >

void Options::Parser< OptionList, Group >::parse_file ( const std::string &  file_name )

noexcept

Parse a file containing options.

Parameters

file_name

the path to the file to parse