osvr::typepack Namespace Reference

A simple argument-pack-based metaprogramming library, inspired by and based partially on https://ericniebler.github.io/meta. More...

Classes
struct	always
	A Alias Class that always returns T. More...
struct	compose
	Compose the Alias Classes Fs in the parameter pack Ts. More...
struct	defer
struct	list
	A wrapper for a template parameter pack of types. More...
struct	quote
class	TypeKeyedBase
class	TypeKeyedMap
	A class that uses types as an index into a container with uniform-typed contents, somewhat like a map except all elements are default-constructed rather than having an optional "not set" status. (You may emulate this by providing a specialization of boost::optional<> as your value type.) More...
class	TypeKeyedTuple
	Provides a data structure where a value of heterogeneous data types may be stored at runtime for each of the "key" types in a list. The runtime data type stored is computed by an alias class. More...

Typedefs
template<typename... Bools>
using	and_ = t_< detail::and_impl< Bools...>>
template<typename F , typename... Args>
using	apply = typename F::template apply< Args...>
	Apply an alias class.
template<typename F , typename Args >
using	apply_list = apply< detail::apply_list_< F, Args >>
	Apply an alias class, exploding the list of args.
template<bool V>
using	bool_ = std::integral_constant< bool, V >
	Alias template to simplify creating a boolean integral constant.
template<typename... Ts>
using	coerce_list = t_< list< Ts...>>
	Will turn whatever is passed into it into the simplest list.
template<typename... Lists>
using	concat = t_< detail::concat_< Lists...>>
template<typename Haystack , typename Needle >
using	contains = apply_list< quote< or_ >, transform< Haystack, detail::is_< Needle >>>
	Determines if type Needle is in the list Haystack - is an alias for a type that inherits std::true_type or std::false_type.
template<typename List , typename Needle >
using	find_first = t_< detail::find_first_impl< Needle, 0, List >>
	Returns the zero-based index of the first instance of Needle in List. Will fail to compile if not found.
template<typename List , typename State , typename Fun >
using	fold = t_< detail::fold_< List, State, Fun >>
	Fold the list (right) with the given alias class and initial state.
template<typename T >
using	has_type = t_< detail::has_type_< T >>
template<typename... Args>
using	if_ = t_< detail::if_impl< Args...>>
template<bool If, typename... Args>
using	if_c = t_< detail::if_impl< bool_< If >, Args...>>
	Select one type or another depending on a compile-time Boolean value.
template<typename Bool >
using	not_ = bool_<!Bool::value >
	Logical not on a single boolean.
template<typename... Bools>
using	or_ = t_< detail::or_impl< Bools...>>
template<template< typename...> class C>
using	quote_trait = compose< quote< t_ >, quote< C >>
	Turn a trait C into a Alias Class.
template<typename... Ts>
using	size = detail::size< coerce_list< Ts...>>
	Get the size of a list (number of elements.)
template<typename... Ts>
using	length = size< coerce_list< Ts...>>
	Synonym for typepack::size.
template<std::size_t V>
using	size_t_ = std::integral_constant< std::size_t, V >
	Alias template to simplify creating an integral constant of size_t.
template<typename... List>
using	head = typename detail::split_list_< List...>::head
	Get the first element of a list.
template<typename... List>
using	tail = typename detail::split_list_< List...>::tail
	Get the list without its first element.
template<typename T >
using	t_ = typename T::type
	A convenience alias template to extract the nested type within the supplied T. More...
template<typename List , typename Fun >
using	transform = t_< detail::transform_< List, Fun >>
template<typename... Ts>
using	void_ = apply< always< void >, Ts...>
	An alias for void.

Functions
template<typename List , typename F , typename... Args>
void	for_each_type (F &&f, Args &&...args)

Detailed Description

A simple argument-pack-based metaprogramming library, inspired by and based partially on https://ericniebler.github.io/meta.

It includes an as-needed subset of the features of meta, modified as needed to build on MSVC 2013, as well as additional functionality not found in meta.

Typedef Documentation

template<typename... Bools>

using osvr::typepack::and_ = typedef t_<detail::and_impl<Bools...>>

Logically and together all the integral constant-wrapped Boolean parameters, with short-circuiting.

Definition at line 61 of file And.h.

template<typename... Lists>

using osvr::typepack::concat = typedef t_<detail::concat_<Lists...>>

Concatenates several lists into a single list.

Precondition

The parameters must all be instantiations of typepack::list.

Complexity

where is the number of lists in the list of lists.

Definition at line 75 of file Concat.h.

template<typename T >

using osvr::typepack::has_type = typedef t_<detail::has_type_<T>>

An alias for std::true_type if T::type exists and names a type; otherwise, it's an alias for std::false_type.

Definition at line 57 of file HasType.h.

template<typename... Args>

using osvr::typepack::if_ = typedef t_<detail::if_impl<Args...>>

Select one type or another depending on a compile-time Boolean integral constant type.

Definition at line 61 of file If.h.

template<typename... Bools>

using osvr::typepack::or_ = typedef t_<detail::or_impl<Bools...>>

Logically or together all the integral constant-wrapped Boolean parameters, with short-circuiting.

Definition at line 58 of file Or.h.

template<typename T >

using osvr::typepack::t_ = typedef typename T::type

A convenience alias template to extract the nested type within the supplied T.

The name was chosen to parallel how the traits in C++14 (like std::enable_if) have been complemented by aliases ending in _t (like std::enable_if_t<COND> being equivalent to typename std::enable_if<COND>::type)

Note that the name is t_, unlike in meta where the semi-illegal name _t is used. (Leading underscores are between risky and not permitted.)

Definition at line 52 of file T.h.

template<typename List , typename Fun >

using osvr::typepack::transform = typedef t_<detail::transform_<List, Fun>>

Given a list and an alias class, apply the alias class to each element in the list and return the results in a list.

Definition at line 54 of file Transform.h.

Function Documentation

template<typename List , typename F , typename... Args>

void osvr::typepack::for_each_type ( F &&  f, Args &&...  args  )

inline

Run-time operation on a type list: given a function object, a type list, and optional arguments to be forwarded to the function call, construct each type in the type list in turn and call the function-call-operator of your functor with it (and your optional additional arguments).

Definition at line 81 of file ForEachType.h.