The ToString class

Class for converting list[int] to strings with specified alphabet.

An instance of this class is callable and used to convert from list[int] to str. The integers in the list are converted to characters according to their position in the alphabet used to construct a ToString instance if one is provided, or using words.human_readable_letter otherwise.

>>> from libsemigroups_pybind11 import ToString
>>> to_string = ToString("bac")
>>> to_string([0, 1, 2])
'bac'
>>> to_string([0, 1, 0, 1, 0, 0, 0, 2, 0, 2])
'bababbbcbc'

>>> to_string.init()      # clear the alphabet
<ToString object with alphabet "">
>>> to_string([0, 1, 2])
'abc'

Contents

`ToString`	Class for converting `list[int]` to strings with specified alphabet.
`ToString.alphabet`(…)	Return the alphabet used for conversion.
`ToString.can_convert_letter`(…)	Check if the current ToString instance can convert a specified letter.
`ToString.copy`(…)	Copy a `ToString` object.
`ToString.empty`(…)	Check if the alphabet is defined.
`ToString.init`(…)	Overloaded function.

Full API

class ToString

__init__(*args, **kwargs)

Overloaded function.

__init__(self: ToString) → None

Default constructor.

Constructs an empty object with no alphabet set.

__init__(self: ToString, alphabet: str) → None

Construct with given alphabet.

Construct a ToString object with the given alphabet.

Parameters:: alphabet (str) – the alphabet.
Raises:: LibsemigroupsError – if there are repeated letters in alphabet.

__call__(self: ToString, input: list[int]) → str

Convert a list[int] to a str.

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

Parameters:: input (list[int]) – the string to convert.
Returns:: The converted string.
Return type:: str
Raises:: LibsemigroupsError – if the alphabet used to define an instance of ToString is not empty and input contains letters that do not correspond to letters of the alphabet.

alphabet(self: ToString) → str

Return the alphabet used for conversion.

This function returns a str corresponding to the ordered-set alphabet \(\{a_0, a_1, \dots, a_{n-1}\}\) that the initialised ToString object will use to convert from list[int] to str. Specifically, \(i \mapsto a_i\) where \(i\) will be an int in a list and \(a_i\) will be a character in a str.

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

Returns:: The alphabet.
Return type:: str

can_convert_letter(self: ToString, l: int) → bool

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

This function returns True if l can be converted to a str using this ToString instance, and False otherwise.

Parameters:: l (int) – the letter to check the convertibility of.
Returns:: Whether the letter can be converted.
Return type:: bool

copy(self: ToString) → ToString

Copy a ToString object.

Returns:: A copy.
Return type:: ToString

empty(self: ToString) → bool

Check if the alphabet is defined.

This function return True if no alphabet has been defined, and False otherwise.

Returns:: A whether the alphabet is empty.
Return type:: bool

init(*args, **kwargs)

Overloaded function.

init(self: ToString) → ToString

Initialize an existing ToString object.

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

Returns:: self.
Return type:: ToString