Abstract base class for regular and multi-value arguments. More...

#include <ookii/command_line_argument.h>

Public Types
using	storage_type = details::argument_storage< CharType, Traits, Alloc >
	The concrete type of argument information storage used. For internal use.

using	string_type = typename storage_type::string_type
	The concrete type of `std::basic_string` used.

using	string_view_type = std::basic_string_view< CharType, Traits >
	The concrete type of `std::basic_string_view` used.

using	usage_options_type = basic_usage_options< CharType, Traits, Alloc >
	The concrete type of `std::basic_usage_options` used.

Public Member Functions
	command_line_argument_base (const command_line_argument_base &)=delete

const std::vector< string_type > &	aliases () const noexcept
	Gets a list of aliases that can be used instead of the argument's name. More...

virtual void	apply_default_value ()=0
	Sets the variable holding the argument's value to the default value. More...

bool	cancel_parsing () const noexcept
	Gets a value that indicates whether supplying this argument will cancel parsing. More...

const string_type &	description () const noexcept
	Gets the long description of the argument. More...

virtual string_type	format_default_value (const usage_options_type &options, const std::locale &loc={}) const =0
	Convert the default value of the argument to a string using the specified usage options. More...

bool	has_value () const noexcept
	Gets a value that indicates whether the argument was specified on the last invocation of basic_command_line_parser::parse(). More...

virtual bool	is_multi_value () const noexcept
	Gets a value that indicates whether the argument can be provided more than once, collecting all the specified values. More...

bool	is_required () const noexcept
	Gets a value that indicates whether the argument is required. More...

virtual bool	is_switch () const noexcept=0
	Gets a value that indicates whether the argument is a switch, which means it can be supplied without a value. More...

const string_type &	name () const noexcept
	Gets the name of the argument. More...

command_line_argument_base &	operator= (const command_line_argument_base &)=delete

std::optional< size_t >	position () const noexcept
	Gets the position of the argument. More...

virtual void	reset ()
	Resets the argument to indicate it hasn't been set. More...

virtual bool	set_switch_value ()=0
	Applies the implicit value for a switch argument. More...

virtual bool	set_value (string_view_type value, std::locale loc={})=0
	Sets the argument to the specified value. More...

const string_type &	value_description () const noexcept
	Gets the value description for the argument. More...

Protected Member Functions
	command_line_argument_base (storage_type &&storage)
	Move constructor for command_line_argument_base.

const storage_type &	base_storage () const
	Provides access to the storage fields to derived classes.

void	set_value () noexcept
	Used to indicate that the argument has a value. More...

Static Protected Member Functions
template<typename T >
static string_type	format_default_value_helper (const std::optional< T > &value, const usage_options_type &options, const std::locale &loc={})
	Helper function for derived classes to implement format_default_value(). More...

Detailed Description

template<typename CharType, typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>
class ookii::command_line_argument_base< CharType, Traits, Alloc >

Abstract base class for regular and multi-value arguments.

Template Parameters

CharType	The character type used for arguments and other strings.
Traits	The character traits to use for strings. Defaults to `std::char_traits<CharType>`.
Alloc	The allocator to use for strings. Defaults to `std::allocator<CharType>`.

This class provides the common functionality for both regular and multi-value arguments.

Member Function Documentation

◆ aliases()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

const std::vector<string_type>& ookii::command_line_argument_base< CharType, Traits, Alloc >::aliases ( ) const

inlinenoexcept

Gets a list of aliases that can be used instead of the argument's name.

An argument may not have any aliases.

Aliases can be added using the basic_parser_builder::argument_builder::alias() method.

◆ apply_default_value()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual void ookii::command_line_argument_base< CharType, Traits, Alloc >::apply_default_value ( )

pure virtual

Sets the variable holding the argument's value to the default value.

This method has no effect if the argument was supplied on the command line (has_value() returns true) or no default value was specified.

For a multi-value argument, the default value will be added as the only value in the container if no values were supplied on the command line.

The default value for an argument can be specified using basic_parser_builder::argument_builder::default_value().

Implemented in ookii::multi_value_command_line_argument< T, CharType, Traits, Alloc >, and ookii::command_line_argument< T, CharType, Traits, Alloc >.

◆ cancel_parsing()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

bool ookii::command_line_argument_base< CharType, Traits, Alloc >::cancel_parsing ( ) const

inlinenoexcept

Gets a value that indicates whether supplying this argument will cancel parsing.

If this returns true, if this argument is supplied, argument parsing will immediately return with parse_error::parsing_cancelled. Arguments after this one will not be evaluated.

This can be used, for example, to implement a -Help argument where usage help should be shown when supplied even if the rest of the command line is valid.

This value can be changed using the basic_parser_builder::argument_builder::cancel_parsing() method.

◆ description()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

const string_type& ookii::command_line_argument_base< CharType, Traits, Alloc >::description ( ) const

inlinenoexcept

Gets the long description of the argument.

The description is used when generating usage help, and is included in the list of descriptions after the usage syntax.

An argument without a description will not be included in the list of descriptions (but will still be included in the syntax).

This value can be changed using the basic_parser_builder::argument_builder::description() method.

◆ format_default_value()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual string_type ookii::command_line_argument_base< CharType, Traits, Alloc >::format_default_value	(	const usage_options_type &	options,
		const std::locale &	loc = `{}`
	)		const

pure virtual

Convert the default value of the argument to a string using the specified usage options.

Parameters

options	The usage options specifying the default value format string.
loc	The locale used to format the value.

Returns: The formatted default value, or an empty string if the argument doesn't have a default value or the options indicate to exclude it.

With the default options, this will return a string like "Default value: value".

The default value for an argument can be specified using basic_parser_builder::argument_builder::default_value().

◆ format_default_value_helper()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

template<typename T >

static string_type ookii::command_line_argument_base< CharType, Traits, Alloc >::format_default_value_helper	(	const std::optional< T > &	value,
		const usage_options_type &	options,
		const std::locale &	loc = `{}`
	)

inlinestaticprotected

Helper function for derived classes to implement format_default_value().

Template Parameters

T	The type of the argument.

Parameters

value	The argument's default value.
options	The usage options specifying the default value format string.
loc	The locale used to format the value.

Returns: The formatted default value, or an empty string if the argument doesn't have a default value or the options indicate to exclude it.

◆ has_value()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

bool ookii::command_line_argument_base< CharType, Traits, Alloc >::has_value ( ) const

inlinenoexcept

Gets a value that indicates whether the argument was specified on the last invocation of basic_command_line_parser::parse().

This allows you to determine if an argument was explicitly specified with a value that matches the default value.

◆ is_multi_value()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual bool ookii::command_line_argument_base< CharType, Traits, Alloc >::is_multi_value ( ) const

inlinevirtualnoexcept

Gets a value that indicates whether the argument can be provided more than once, collecting all the specified values.

An argument is multi-value if it was created using basic_parser_builder::add_multi_value_argument().

Reimplemented in ookii::multi_value_command_line_argument< T, CharType, Traits, Alloc >.

◆ is_required()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

bool ookii::command_line_argument_base< CharType, Traits, Alloc >::is_required ( ) const

inlinenoexcept

Gets a value that indicates whether the argument is required.

A required argument must be provided, otherwise parsing is not successful.

An argument can be made required using the basic_parser_builder::argument_builder::required() method.

◆ is_switch()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual bool ookii::command_line_argument_base< CharType, Traits, Alloc >::is_switch ( ) const

pure virtualnoexcept

Gets a value that indicates whether the argument is a switch, which means it can be supplied without a value.

An argument is a switch if its type is bool or std::optional<bool>.

Implemented in ookii::multi_value_command_line_argument< T, CharType, Traits, Alloc >, and ookii::command_line_argument< T, CharType, Traits, Alloc >.

◆ name()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

const string_type& ookii::command_line_argument_base< CharType, Traits, Alloc >::name ( ) const

inlinenoexcept

Gets the name of the argument.

The argument's name is set using the basic_parser_builder::add_argument() method.

◆ position()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

std::optional<size_t> ookii::command_line_argument_base< CharType, Traits, Alloc >::position ( ) const

inlinenoexcept

Gets the position of the argument.

Returns: The position, or std::nullopt if the argument is not positional.

A positional argument can be specified without suppling -Name before the value. Note that a positional argument can still be specified by name, as well as by position.

An argument can be made positional using the basic_parser_builder::argument_builder::positional() method.

◆ reset()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual void ookii::command_line_argument_base< CharType, Traits, Alloc >::reset ( )

inlinevirtual

Resets the argument to indicate it hasn't been set.

The reset() method is called on all arguments before parsing. After the call, the has_value() method will return false. This method does not affect the value of the variable holding the argument's value, except for multi-value arguments, where the container holding the values is cleared before parsing.

Reimplemented in ookii::multi_value_command_line_argument< T, CharType, Traits, Alloc >.

◆ set_switch_value()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual bool ookii::command_line_argument_base< CharType, Traits, Alloc >::set_switch_value ( )

pure virtual

Applies the implicit value for a switch argument.

Returns: true if the argument was a switch argument; otherwise, false.

If the argument is a switch argument (is_switch() returns true), the variable holding its variable will be set to true. Otherwise, the value is not changed and false is returned.

For a multi-value argument, this adds a value of true to the container.

Implemented in ookii::multi_value_command_line_argument< T, CharType, Traits, Alloc >, and ookii::command_line_argument< T, CharType, Traits, Alloc >.

◆ set_value() [1/2]

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

void ookii::command_line_argument_base< CharType, Traits, Alloc >::set_value ( )

inlineprotectednoexcept

Used to indicate that the argument has a value.

After calling this method, has_value() will return true.

◆ set_value() [2/2]

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

virtual bool ookii::command_line_argument_base< CharType, Traits, Alloc >::set_value	(	string_view_type	value,
		std::locale	loc = `{}`
	)

pure virtual

Sets the argument to the specified value.

Parameters

value	The string value of the argument.
loc	The locale to use to parse the argument value.

Returns: true if the value was successfully set, or false if conversion to the argument's type failed.

When the value is set, this method converts to the string value to the actual type of the argument using either the custom converter function (if any), or the default converter, which is the lexical_convert template.

For multi-value arguments, the new value will be added to the list of values.

◆ value_description()

template<typename CharType , typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>

const string_type& ookii::command_line_argument_base< CharType, Traits, Alloc >::value_description ( ) const

inlinenoexcept

Gets the value description for the argument.

The value description is a brief, often one-word description of the type of values that the argument accepts. It's used as part of the usage help's syntax.

This value defaults to the short type name (excluding namespace names) of the argument's type. The exact value may depend on your compiler.

This value can be changed using the basic_parser_builder::argument_builder::value_description() method.

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

/mnt/d/Sven/Documents/Code/Ookii.CommandLine.Cpp/include/ookii/command_line_argument.h

Public Types

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Detailed Description

template<typename CharType, typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>> class ookii::command_line_argument_base< CharType, Traits, Alloc >

Member Function Documentation

◆ aliases()

◆ apply_default_value()

◆ cancel_parsing()

◆ description()

◆ format_default_value()

◆ format_default_value_helper()

◆ has_value()

◆ is_multi_value()

◆ is_required()

◆ is_switch()

◆ name()

◆ position()

◆ reset()

◆ set_switch_value()

◆ set_value() [1/2]

◆ set_value() [2/2]

◆ value_description()

template<typename CharType, typename Traits = std::char_traits<CharType>, typename Alloc = std::allocator<CharType>>
class ookii::command_line_argument_base< CharType, Traits, Alloc >