SCREAMINGSNAKECASE

SCREAMING_SNAKE_CASE, often written as SCREAMING_SNAKE_CASE, is a naming convention used in programming where identifiers are written in all uppercase letters with underscores between words. The term “screaming” reflects the uppercase, attention-grabbing appearance. This style is a subset of snake_case, distinguished by the use of uppercase letters to signal constants or fixed values.

Common use cases include naming constants, macros, and environment variables. In many languages, identifiers that should not change at runtime or that represent fixed configuration are written in this form to distinguish them from regular variables. It maps well to macro definitions in C and C++, to constant fields in Java, and to constant values in Python and JavaScript.

Compared with snake_case (lowercase with underscores) and camelCase or PascalCase, SCREAMING_SNAKE_CASE uses uppercase letters exclusively. It is not typically used for ordinary variables or function names, except where a project or language convention explicitly treats all constants this way.

Language-specific practices vary. Python’s PEP 8 suggests ALL_CAPS for module or class constants by convention. Java often uses public static final fields in ALL_CAPS with underscores. C and C++ frequently capitalize macros and constants. Environment variables, especially on UNIX-like systems, are commonly all caps with underscores (e.g., PATH, CONFIG_DIR).

Examples include MAX_BUFFER_SIZE, DEFAULT_TIMEOUT_SECONDS, APP_VERSION. While widely used, practitioners should follow project style guides, maintain readability, and avoid overly long identifiers when possible.