seqan3::alphabet_proxy< derived_type, alphabet_type > Class Template Reference

A CRTP-base that eases the definition of proxy types returned in place of regular alphabets. More...

#include <seqan3/alphabet/detail/alphabet_proxy.hpp>

Inheritance diagram for seqan3::alphabet_proxy< derived_type, alphabet_type >:

Public Member Functions
Write functions
All of these call the emulated type's write functions and then delegate to the assignment operator which invokes derived behaviour.
constexpr derived_type &	assign_rank (alphabet_rank_t< alphabet_type > const r) noexcept
	Assigns a rank.
constexpr derived_type &	assign_char (char_type const c) noexcept
	Assigns a character.
constexpr derived_type &	assign_phred (phred_type const c) noexcept
	Assigns a phred.

Static Public Attributes
static constexpr auto	alphabet_size = seqan3::alphabet_size<alphabet_type>
	The alphabet size.

Read functions
All of these call the emulated type's read functions.
constexpr	operator alphabet_type () const noexcept
	Implicit conversion to the emulated type.
template<typename other_t >
constexpr	operator other_t () const noexcept
	Implicit conversion to types that the emulated type is convertible to.
constexpr auto	to_rank () const noexcept
	Returns the rank.
constexpr auto	to_char () const noexcept
	Returns the character.
constexpr auto	to_phred () const noexcept
	Returns the phred score.
constexpr alphabet_type	complement () const noexcept
	Returns the complement.
static constexpr bool	char_is_valid (char_type const c) noexcept
	Delegate to the emulated type's validator.

Comparison operators
These are only required if the emulated type allows comparison with types it is not convertible to, e.g. seqan3::alphabet_variant.
template<typename t >
constexpr friend auto	operator== (derived_type const lhs, t const rhs) noexcept -> std::enable_if_t< is_alphabet_comparable_with< t >, bool >
	Allow (in-)equality comparison with types that the emulated type is comparable with.
template<typename t >
constexpr friend auto	operator== (t const lhs, derived_type const rhs) noexcept -> std::enable_if_t< is_alphabet_comparable_with< t >, bool >
	Allow (in-)equality comparison with types that the emulated type is comparable with.
template<typename t >
constexpr friend auto	operator!= (derived_type const lhs, t const rhs) noexcept -> std::enable_if_t< is_alphabet_comparable_with< t >, bool >
	Allow (in-)equality comparison with types that the emulated type is comparable with.
template<typename t >
constexpr friend auto	operator!= (t const lhs, derived_type const rhs) noexcept -> std::enable_if_t< is_alphabet_comparable_with< t >, bool >
	Allow (in-)equality comparison with types that the emulated type is comparable with.

Detailed Description

template<typename derived_type, writable_semialphabet alphabet_type>
class seqan3::alphabet_proxy< derived_type, alphabet_type >

A CRTP-base that eases the definition of proxy types returned in place of regular alphabets.

Template Parameters

derived_type	The CRTP parameter type.
alphabet_type	The type of the alphabet that this proxy emulates; must model at least seqan3::writable_semialphabet and std::regular.

Warning

This documentation item is not guaranteed to exist in future SeqAn3 releases. Do not rely on the interface in your applications.

Certain containers and other data structure hold alphabet values in a non-standard way so they can convert to that alphabet when being accessed, but cannot return a reference to the held value. These data structures may instead return a proxy to the held value which still allows changing it (and updating the underlying data structure to reflect this).

This CRTP base facilitates the definition of such proxies. Most users of SeqAn will not need to understand the details.

This class ensures that the proxy itself also models seqan3::semialphabet, seqan3::alphabet, seqan3::quality_alphabet, seqan3::nucleotide_alphabet and/or seqan3::aminoacid_alphabet if the emulated type models these. This makes sure that function templates which accept the original, also accept the proxy.

Implementation notes

The derived type needs to provide an .on_update() member function that performs the changes in the underlying data structure.

See seqan3::bitcompressed_vector or seqan3::alphabet_tuple_base for examples of how this class is used.

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

• seqan3/alphabet/detail/alphabet_proxy.hpp