ToWord< From >

template<typename From>
class libsemigroups::v4::ToWord< From >

Defined in word-range.hpp.

An instance of this class is used to convert from std::string to word_type. The characters in the string are converted to integers according to their position in alphabet used to construct a ToWord instance if one is provided, or using human_readable_index otherwise.

Example

ToWord toword("bac");
toword("bac");        // returns {0, 1, 2}
toword("bababbbcbc"); // returns { 0, 1, 0, 1, 0, 0, 0, 2, 0, 2}
 
toword.init();
toword("bac");        // returns {1, 0, 2}

Public Types
using	from_type = From
	The type of values an instance of ToWord will convert into word_type.

Public Member Functions
	ToWord ()
	Default constructor.
	ToWord (From const &alphabet)
	Construct with given alphabet.
	ToWord (ToWord &&)
	Default move constructor.
	ToWord (ToWord const &)
	Default copy constructor.
from_type	alphabet () const
	Return the alphabet used for conversion.
word_type	call_no_checks (From const &input) const
	Convert a string to a word_type.
letter_type	call_no_checks (typename From::value_type input) const
	Convert a char to a letter_type.
void	call_no_checks (word_type &output, From const &input) const
	Convert a string to a word_type.
bool	can_convert_letter (typename from_type::value_type const &c) const
bool	empty () const noexcept
	Check if the alphabet is defined.
ToWord &	init ()
	Initialize an existing ToWord object.
ToWord &	init (From const &alphabet)
	Initialize an existing ToWord object.
word_type	operator() (From const &input) const
	Convert a string to a word_type.
template<typename InputRange, typename = std::enable_if_t<rx::is_input_or_sink_v<InputRange>>>
constexpr auto	operator() (InputRange &&input) const
	Call operator for combining with other range objects.
letter_type	operator() (typename From::value_type input) const
	Convert a char to a letter_type.
void	operator() (word_type &output, From const &input) const
	Convert a string to a word_type.
ToWord &	operator= (ToWord &&)
	Default move assignment.
ToWord &	operator= (ToWord const &)
	Default copy assignment.

Constructor & Destructor Documentation

ToWord() [1/4]

template<typename From>

ToWord ( )

inline

Constructs an empty object with no alphabet set.

ToWord() [2/4]

template<typename From>

ToWord ( ToWord< From > const & )

default

Default copy constructor.

ToWord() [3/4]

template<typename From>

ToWord ( ToWord< From > && )

default

Default move constructor.

ToWord() [4/4]

template<typename From>

ToWord ( From const & alphabet )

inlineexplicit

Construct a ToWord object with the given alphabet.

Parameters

alphabet

the alphabet.

Exceptions

LibsemigroupsException

if there are repeated letters in alphabet.

Member Function Documentation

alphabet()

template<typename From>

From alphabet ( ) const

nodiscard

This function returns a std::string corresponding to the ordered-set alphabet \(\{a_0, a_1, \dots, a_{n-1}\}\) that the initialised ToWord object will use to convert from std::string to word_type. Specifically, \(a_i \mapsto i\) where \(a_i\) will correspond to a letter in a std::string, and \(i\) is a letter_type.

If this function returns the empty string, then conversion will be performed using human_readable_index.

Returns

A value of type std::string.

Exceptions

This function guarantees not to throw a LibsemigroupsException..

call_no_checks() [1/3]

template<typename From>

word_type call_no_checks ( From const & input ) const

inlinenodiscard

This function converts its argument input into a word_type. The characters of input are converted using the alphabet used to construct the object or set via init(), or with human_readable_index if empty returns true.

Parameters

input

the string to convert.

Warning

This functions performs no checks on its arguments. In particular, if the alphabet used to define an instance of ToWord is not empty, and input contains letters that do not correspond to letters of the alphabet, then bad things will happen.

See also

• literals

call_no_checks() [2/3]

template<typename From>

letter_type call_no_checks ( typename From::value_type input ) const

inlinenodiscard

This function converts its argument input into a letter_type. It is converted using the alphabet used to construct the object or set via init(), or with human_readable_index if empty returns true.

Parameters

input

the character to convert.

Warning

This functions performs no checks on its arguments. In particular, if the alphabet used to define an instance of ToWord is not empty, and input does not correspond to a letter of the alphabet, then bad things will happen.

See also

• literals

call_no_checks() [3/3]

template<typename From>

void call_no_checks	(	word_type &	output,
		From const &	input ) const

This function converts its second argument input into a word_type and stores the result in the first argument output. The characters of input are converted using the alphabet used to construct the object or set via init(), or with human_readable_index if empty returns true.

The contents of the first argument output, if any, is removed.

Parameters

output	word to hold the result.
input	the string to convert.

Warning

This functions performs no checks on its arguments. In particular, if the alphabet used to define an instance of ToWord is not empty, and input contains letters that do not correspond to letters of the alphabet, then bad things will happen.

See also

• literals

can_convert_letter()

template<typename From>

bool can_convert_letter ( typename from_type::value_type const & c ) const

inlinenodiscard

Check if the current ToWord instance can convert a specified letter.

This function returns true if c can can be converted to a letter_type using this ToWord instance, and false otherwise.

Parameters

c	the char to check the convertibility of.

Returns

A value of type bool.

Exceptions

This function guarantees not to throw a LibsemigroupsException.

empty()

template<typename From>

bool empty ( ) const

inlinenodiscardnoexcept

This function returns true if no alphabet has been defined, and false otherwise.

Returns

A value of type bool.

Exceptions

This function is noexcept and is guaranteed never to throw.

init() [1/2]

template<typename From>

ToWord & init ( )

inline

This function puts a ToWord object back into the same state as if it had been newly default constructed.

Returns

A reference to *this.

Exceptions

This function guarantees not to throw a LibsemigroupsException.

See also

ToWord()

init() [2/2]

template<typename From>

ToWord< From > & init

(

From const &

alphabet

)

This function puts a ToWord object back into the same state as if it had been newly constructed from alphabet.

Parameters

alphabet

the alphabet.

Returns

A reference to *this.

Exceptions

LibsemigroupsException

if there are repeated letters in alphabet.

See also

ToWord(From const& alphabet)

operator()() [1/4]

template<typename From>

word_type operator() ( From const & input ) const

inlinenodiscard

This function converts its argument input into a word_type The characters of input are converted using the alphabet used to construct the object or set via init(), or with human_readable_index if empty returns true.

Parameters

input

the string to convert.

Exceptions

LibsemigroupsException

if the alphabet used to define an instance of ToWord is not empty and input contains letters that do not correspond to letters of the alphabet.

See also

• literals

operator()() [2/4]

template<typename From>

template<typename InputRange, typename = std::enable_if_t<rx::is_input_or_sink_v<InputRange>>>

auto operator() ( InputRange && input ) const

inlinenodiscardconstexpr

A custom combinator for rx::ranges to convert the output of a StringRange object into word_type, that can be combined with other combinators using operator|.

Example

StringRange strings;
strings.alphabet("ab").first("a").last("bbbb");
auto words = (strings | ToWord("ba"));
// contains the words
// {1_w,    0_w,    11_w,   10_w,   01_w,   00_w,   111_w,
//  110_w,  101_w,  100_w,  011_w,  010_w,  001_w,  000_w,
//  1111_w, 1110_w, 1101_w, 1100_w, 1011_w, 1010_w, 1001_w,
//  1000_w, 0111_w, 0110_w, 0101_w, 0100_w, 0011_w, 0010_w,
//  0001_w}));

operator()() [3/4]

template<typename From>

letter_type operator() ( typename From::value_type input ) const

inlinenodiscard

This function converts its argument input into a letter_type. It is converted using the alphabet used to construct the object or set via init(), or with human_readable_index if empty returns true.

Parameters

input

the character to convert.

Exceptions

LibsemigroupsException

if the alphabet used to define an instance of ToWord is not empty and input does not correspond to a letter of the alphabet.

See also

• literals

operator()() [4/4]

template<typename From>

void operator()	(	word_type &	output,
		From const &	input ) const

This function converts its second argument input into a word_type and stores the result in the first argument output. The characters of input are converted using the alphabet used to construct the object or set via init(), or with human_readable_index if empty returns true.

The contents of the first argument output, if any, is removed.

Parameters

output	word to hold the result.
input	the string to convert.

Exceptions

LibsemigroupsException

if the alphabet used to define an instance of ToWord is not empty and input contains letters that do not correspond to letters of the alphabet.

See also

• literals

operator=() [1/2]

template<typename From>

ToWord< From > & operator= ( ToWord< From > && )

default

Default move assignment.

operator=() [2/2]

template<typename From>

ToWord< From > & operator= ( ToWord< From > const & )

default

Default copy assignment.

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

• /Users/jdm3/libsemigroups/include/libsemigroups/word-range.hpp