Metaprogramming rlang

This skill covers modern rlang patterns for data-masking, tidy evaluation, and building programmatic tidyverse functions.

Core Concepts

Data-masking allows R expressions to refer to data frame columns as if they were variables in the environment. rlang provides the metaprogramming framework that powers tidyverse data-masking.

Key rlang Tools

• Embracing {{}} - Forward function arguments to data-masking functions
• Injection !! - Inject single expressions or values
• Splicing !!! - Inject multiple arguments from a list
• Dynamic dots - Programmable ... with injection support
• Pronouns .data/.env - Explicit disambiguation between data and environment variables

When to Use Each Operator