python

anycase

💼 A case conversion library for Python.

Features

• Automatic case detection, no need to specify the input case
• Extremely fast, written in Rust ✨
• Support for Unicode characters
• Support for providing acronyms in title case

🚀 Getting started

Install using

pip install py-anycase

Now convert a string using the relevant function.

import anycase

anycase.to_snake("XMLHttpRequest") # returns "xml_http_request"

🤸 Usage

The py-anycase package provides a set of functions to convert strings between different case styles. The following cases are available.

Function	Output
anycase.to_camel(s)	camelCase
anycase.to_pascal(s)	PascalCase
anycase.to_snake(s)	snake_case
anycase.to_screaming_snake(s)	SCREAMING_SNAKE_CASE
anycase.to_kebab(s)	kebab-case
anycase.to_screaming_kebab(s)	SCREAMING-KEBAB-CASE
anycase.to_train(s)	Train-Case
anycase.to_lower(s)	lower case
anycase.to_title(s)	Title Case
anycase.to_upper(s)	UPPER CASE

Additionally, functions where the "word function" is "title" accept an optional acronyms argument, which is a mapping of lowercase words to their output. For example:

>>> anycase.to_pascal("xml_http_request", acronyms={"xml": "XML"})
'XMLHttpRequest'
>>> anycase.to_pascal("xml_http_request", acronyms={"xml": "XML", "http": "HTTP"})
'XMLHTTPRequest'

How does it work?

This implementation divides the input string into words and applies a "word function" to each word and calls a "delimiter function" for each word boundary (the space between words).

Word boundaries are defined as follows:

• A set of consecutive non-letter/number/symbol e.g. foo _bar is two words foo and bar.
• A transition from a lowercase letter to an uppercase letter e.g. fooBar is two words foo and Bar.
• The second last uppercase letter in a word with multiple uppercase letters e.g. FOOBar is two words FOO and Bar.

Benchmarks

A simple benchmark against various other libraries is provided in ./benches. The following table shows the results when run on my Macbook M2 Max.

Library	Min (µs)	Max (µs)	Mean (µs)
py-anycase	26.666	176.834	30.909
pyheck	51.000	131.416	53.565
pure python	63.583	108.125	65.075
re	81.916	171.000	87.856
stringcase	99.250	222.292	102.197
pydantic.alias_generators	182.000	304.458	189.063
inflection	229.750	360.792	239.153
caseconversion	1,430.042	1,838.375	1,559.019

License

This project is distributed under the terms of both the MIT license and the Apache License (Version 2.0).

See LICENSE-APACHE and LICENSE-MIT for details.