R Code Patterns for Packages

Using library() and source() in R package code breaks namespace management and creates unpredictable state. Instead, use pkg::fun() or @importFrom directives to declare dependencies, ensuring robust and maintainable package behavior.

To properly import functions for R package development, use explicit namespace calls like pkg::fun() or add @importFrom directives in your Roxygen tags. This ensures dependencies are declared correctly without loading entire packages.

Build-time execution in R packages runs code when the package is compiled, while load-time execution runs when a user loads the package. Understanding this distinction is critical for safe global state manipulation and avoiding unexpected side effects.

Use requireNamespace() in R package development for conditional dependency checks, allowing graceful fallback if a package is missing. Unlike library(), it returns a boolean and avoids altering the search path, maintaining namespace integrity.

The triple colon ::: accesses internal package objects and is forbidden in R package code because it bypasses namespace management, creating fragile dependencies on unexported API elements. Stick to exported functions via pkg::fun() or @importFrom.

Non-ASCII characters in R scripts are forbidden in R package development because they cause encoding issues during package building and testing. R package code best practices require sticking to ASCII characters to ensure cross-platform compatibility.