Snake case

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Piece of code from a module of the Linux kernel, which uses snake case for identifiers. Alx source snippet.png
Piece of code from a module of the Linux kernel, which uses snake case for identifiers.

Snake case (stylized as snake_case) is the naming convention in which each space is replaced with an underscore (_) character, and words are written in lowercase. It is a commonly used naming convention in computing, for example for variable and subroutine names, and for filenames. One study has found that readers can recognize snake case values more quickly than camel case. However, "subjects were trained mainly in the underscore style", so the possibility of bias cannot be eliminated. [1]

Contents

A variation is screaming snake case where words are written in all caps (stylized as SCREAMING_SNAKE_CASE). [2] This convention is used for constants in programming languages like C/C++, Python, Java , PHP, as well as for environment variables.

History

The use of underscores as word separators dates back to the late 1960s. It is particularly associated with C, is found in The C Programming Language (1978), and contrasted with pascal case (a type of camel case). However, the convention traditionally had no specific name: the Python programming language style guide refers to it simply as "lower_case_with_underscores". [3]

Within Usenet the term snake_case was first seen in the Ruby community in 2004, [4] used by Gavin Kistner, writing:

BTW...what *do* you call that naming style? snake_case? That's what I'll call it until someone corrects me.

However, former Intel engineer Jack Dahlgren has stated that he was using the term internally at Intel (and perhaps in dialogue with Microsoft engineers) in 2002. [5] [ failed verification ] It is possible that the term developed independently in more than one community.

As of 2015, names for other delimiter-separated naming conventions for multiple-word identifiers have not been standardized, although some terms have increasing levels of usage, such as lisp-case, kebab-case, SCREAMING_SNAKE_CASE, and more. [6] [7] [8]

Examples

The following programming languages use snake case by convention:

See also

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References

  1. ↑ Sharif, Bonita; Maletic, Jonathan I. (2010). "An Eye Tracking Study on camelCase and under_score Identifier Styles". 2010 IEEE 18th International Conference on Program Comprehension (PDF). pp. 196–205. CiteSeerX   10.1.1.421.6137 . doi:10.1109/ICPC.2010.41. ISBN   978-1-4244-7604-6. S2CID   14170019.
  2. ↑ "Snake Case". Mozilla Developer Network. Retrieved November 10, 2023.
  3. 1 2 Guido van Rossum; Barry Warsaw; Nick Coghlan (2001-07-05). "PEP 0008 -- Style Guide for Python Code".
  4. ↑ Gavin Kistner (2004-02-23). "Appropriate use of camelCase". Newsgroup:  comp.lang.ruby. Usenet:   HBn_b.379957$xy6.2073499@attbi_s02 . Retrieved 2015-08-13.
  5. ↑ "Quora". 2013-05-10.
  6. ↑ "StackOverflow – What's the name for snake_case with dashes?".
  7. ↑ "Programmers – If this is camelCase what-is-this?". Archived from the original on 2016-08-07. Retrieved 2015-08-13.
  8. ↑ "Camel_SNAKE-kebab". GitHub . 23 April 2020.
  9. ↑ "Naming Conventions in ABAP Objects". help.sap.com. Retrieved 2020-07-28.
  10. ↑ "Ada Programming Guidelines".
  11. ↑ "Boost Library Requirements and Guidelines" . Retrieved 2015-08-13.
  12. ↑ "Eiffel Class and Feature Names". 28 December 2019.
  13. ↑ "Elixir Style Guide". GitHub . May 2020.
  14. ↑ "Programming Rules". Archived from the original on 2010-09-04. Retrieved 2017-08-11.
  15. ↑ "GDScript Style Guide".
  16. ↑ "Code Conventions for the Java Programming Language – Naming Conventions". Oracle. Retrieved 2021-08-03.
  17. ↑ "Coding Conventions" . Retrieved 2023-02-03.
  18. ↑ "Xen wiki" . Retrieved 2017-03-15.
  19. ↑ Damian Conway (2005). Perl Best Practices . O'Reilly Media Inc. p.  44. ISBN   978-0-596-00173-5.
  20. ↑ "Quick Guide to Some Sources for Naming Conventions for Oracle Database Development". stevenfeuersteinonplsql.blogspot.com. Retrieved 2020-12-30.
  21. ↑ Michael A. Covington; Roberto Bagnara; Richard A. O'Keefe; Jan Wielemaker; Simon Price (2009). "Coding Guidelines for Prolog (v.3)". p. 14. arXiv: 0911.2899 [cs.PL].
  22. ↑ IBM (July 1965). IBM Operating System/360 PL/I: Language Specifications (PDF). p. 16. Retrieved November 12, 2023.
  23. ↑ Wickham, Hadley. The tidyverse style guide.
  24. ↑ "Ruby Naming Conventions". GitHub . May 2020.
  25. ↑ "Naming – Rust API Guidelines". Archived from the original on 2018-09-16. Retrieved 2019-10-27.
  26. ↑ "Terraform Naming Conventions". Feb 2022.
  27. ↑ "Documentation - The Zig Programming Language" . Retrieved 2024-03-10.
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