UPPERSNAKECASE

UPPERSNAKECASE is a naming convention used in programming to denote identifiers that are constants or fixed values. It is commonly known as screaming snake case or upper snake case. In this style, words are joined by underscores and written in all capital letters, with no spaces or punctuation beyond the separating underscores. Examples include MAX_VALUE, DEFAULT_TIMEOUT, and DATABASE_URL.

This convention derives from snake_case, where words are lowercase with underscores, but here the entire identifier is uppercase to signal constancy. It is widely used across languages and codebases to distinguish constants from variables and other identifiers.

In practice, UPPERSNAKECASE is recommended for constants, macros, and environment variable names in many style guides. For example, Python's PEP 8 suggests module-level constants be named in uppercase with underscores; Java constants are typically written in uppercase with underscores as well. However, not all languages enforce this; some alternatives use camelCase or PascalCase for constants depending on the language's idioms.

Common variants and synonyms include SCREAMING_SNAKE_CASE, UPPER_SNAKE_CASE, and UPPERCASE_WITH_UNDERSCORES. It is important to maintain consistency within a project, and to avoid using this convention for non-constant identifiers, where readability and language conventions may favor other styles.