darbia.utils.strings

Assorted utility functions.

Module Contents

Classes

CustomEncoder

A custom JSON encoder that attempts to convert all user defined classes to string.

Functions

random_string(→ str)	Generate a random string of the specified length using the specified character set.
split_prefix_and_number(→ tuple[str, int])	Split a string into alpha prefix and numeric suffix.
find_nth(→ int)	Find the nth occurrence of a substring in a string.
bulk_substring_remove(→ str)	Remove all substrings from a string.
prefix_zfilled(→ collections.abc.Iterable[str])	Generate a series of formatted strings from an iterable.

Attributes

T

darbia.utils.strings.T

darbia.utils.strings.random_string(length: int = 6, characters: str = string.ascii_uppercase) → str

Generate a random string of the specified length using the specified character set.

Parameters:

• length – The desired length.

• characters – The character set.

Returns:

result – A random string.

Return type:

str

Examples

>>> random_string(length=1,  characters='a')
'a'

darbia.utils.strings.split_prefix_and_number(text: str) → tuple[str, int]

Split a string into alpha prefix and numeric suffix.

Parameters:

text (str) – The text to split

Returns:

prefix, number – The prefix and the number

Return type:

tuple[str, int]

Examples

>>> split_prefix_and_number('U1500000')
('U', 1500000)

class darbia.utils.strings.CustomEncoder(*, skipkeys=False, ensure_ascii=True, check_circular=True, allow_nan=True, sort_keys=False, indent=None, separators=None, default=None)

Bases: json.JSONEncoder

A custom JSON encoder that attempts to convert all user defined classes to string.

default(o: T) → T

Serialize an object.

If the object is not a builtin, return the __str__ of the object. For builtins, use the standard serializer.

Parameters:

o (Any) – Object to serialize

Returns:

serialized_object – Serialized object

Return type:

Any

darbia.utils.strings.find_nth(haystack: str, needle: str, nth: int) → int

Find the nth occurrence of a substring in a string.

Parameters:

• haystack – The string to search in

• needle – The substring to search for

• nth – Which nth occurrence to find

Return type:

The index of the nth occurrence of the substring, or -1 if not found.

Examples

>>> find_nth("yankee doodle", "o", 2)
9

darbia.utils.strings.bulk_substring_remove(text: str, substrings: list[str]) → str

Remove all substrings from a string.

Parameters:

• text – The string to update

• substrings – The substrings to remove

Return type:

The original string with all substrings removed

Examples

>>> bulk_substring_remove("yankee doodle", ["yan", "dle"])
'kee doo'

darbia.utils.strings.prefix_zfilled(prefix: str, iterable: collections.abc.Iterable, sep: str = '-', zeroes: int = 3) → collections.abc.Iterable[str]

Generate a series of formatted strings from an iterable.

Parameters:

• prefix – The text to prefix to each item

• iterable – The items to iterate over

• sep – The seperator between the prefix and the iterable

• zeroes – The number of zeros to zfill the iterable with

Yields:

The items from the iterable with formatting

Examples

>>> list(prefix_zfilled("x", range(50, 53)))
['x-050', 'x-051', 'x-052']