class option_description

Declaration

class option_description { /* full declaration omitted */ };

Description

Describes one possible command line/config file option. There are two kinds of properties of an option. First describe it syntactically and are used only to validate input. Second affect interpretation of the option, for example default value for it or function that should be called when the value is finally known. Routines which perform parsing never use second kind of properties \ -- they are side effect free.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:36

Method Overview

• public std::string canonical_display_name(int canonical_option_style = 0) const
• public const std::string & description() const
• public std::string format_name() const
• public std::string format_parameter() const
• public const std::string & key(const std::string & option) const
• public const std::string & long_name() const
• public const std::pair<const std::string *, std::size_t> long_names() const
• public pika::program_options::option_description::match_result match(const std::string & option, bool approx, bool long_ignore_case, bool short_ignore_case) const
• public option_description()
• public option_description(const char * name, const pika::program_options::value_semantic * s)
• public option_description(const char * name, const pika::program_options::value_semantic * s, const char * description)
• public std::shared_ptr<const value_semantic> semantic() const
• public virtual ~option_description()

Methods

std::string canonical_display_name(
    int canonical_option_style = 0) const

Description

Returns the canonical name for the option description to enable the user to recognized a matching option. 1) For short options ('-', '/'), returns the short name prefixed. 2) For long options ('--' / '-') returns the first long name prefixed 3) All other cases, returns the first long name (if present) or the short name, un-prefixed.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:104

Parameters

int canonical_option_style = 0

const std::string& description() const

Description

Explanation of this option

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:112

std::string format_name() const

Description

Returns the option name, formatted suitably for usage message.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:118

std::string format_parameter() const

Description

Returns the parameter name and properties, formatted suitably for usage message.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:122

const std::string& key(
    const std::string& option) const

Description

Returns the key that should identify the option, in particular in the variables_map class. The 'option' parameter is the option spelling from the input source. If option name contains '*', returns 'option'. If long name was specified, it's the long name, otherwise it's a short name with pre-pended '-'.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:95

Parameters

const std::string& option

const std::string& long_name() const

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:107

const std::pair<const std::string*, std::size_t>
long_names() const

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:109

pika::program_options::option_description::
    match_result
    match(const std::string& option,
          bool approx,
          bool long_ignore_case,
          bool short_ignore_case) const

Description

Given 'option', specified in the input source, returns 'true' if 'option' specifies *this.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:84

Parameters

const std::string& option

bool approx

bool long_ignore_case

bool short_ignore_case

option_description()

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:39

option_description(
    const char* name,
    const pika::program_options::value_semantic*
        s)

Description

Initializes the object with the passed data. Note: it would be nice to make the second parameter auto_ptr, to explicitly pass ownership. Unfortunately, it's often needed to create objects of types derived from 'value_semantic': options_description d; d.add_options()("a", parameter <int >("n")->default_value(1)); Here, the static type returned by 'parameter' should be derived from value_semantic. Alas, derived->base conversion for auto_ptr does not really work, see http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2000/n1232.pdf http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#84 So, we have to use plain old pointers. Besides, users are not expected to use the constructor directly. The 'name' parameter is interpreted by the following rules: - if there's no "," character in 'name', it specifies long name - otherwise, the part before "," specifies long name and the part after \ -- short name.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:65

Parameters

const char* name

const pika::program_options::value_semantic* s

option_description(
    const char* name,
    const pika::program_options::value_semantic*
        s,
    const char* description)

Description

Initializes the class with the passed data.

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:69

Parameters

const char* name

const pika::program_options::value_semantic* s

const char* description

std::shared_ptr<const value_semantic> semantic()
    const

Description

Semantic of option's value

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:115

virtual ~option_description()

Declared at: libs/pika/program_options/include/pika/program_options/options_description.hpp:72