enum

The enum package provides a robust implementation of enumerations (enums) for R, enabling the creation of type-safe, validated sets of named constants. Enums help prevent errors by constraining variables to predefined values and offer better code readability and maintainability.

Installation

You can install the development version of enum from GitHub with:

# install.packages("pak")
pak::pak("milanmlft/enum")

Example

library(enum)

# Create an enum for days of the week
Days <- Enum(
  MONDAY = 1,
  TUESDAY = 2,
  WEDNESDAY = 3,
  THURSDAY = 4,
  FRIDAY = 5,
  SATURDAY = 6,
  SUNDAY = 7
)

# Use the enum
today <- Days$MONDAY
today
#> [1] 1

Features

• Validation: Values are automatically validated against defined constants
• Readability: Named constants make code more self-documenting
• Maintainability: Centralized definition of related constants

Accessors

Enums support the following accessors:

• $: Access a single value by name
• [[: Access multiple values by name
• names: Get the names of the enum

Days[["MONDAY"]]
#> [1] 1
Days$TUESDAY
#> [1] 2
names(Days)
#> [1] "MONDAY"    "TUESDAY"   "WEDNESDAY" "THURSDAY"  "FRIDAY"    "SATURDAY"
#> [7] "SUNDAY"

Validation

All enum names must be unique and non-empty strings.

Days <- Enum(
  MONDAY = 1,
  MONDAY = 2
)
#> Error: Duplicate enum names

Days <- Enum(
  MONDAY = 1,
  2
)
#> Error: All enum values must be named

Immutability

Enums are immutable, meaning that once created, their values cannot be changed.

Days$MONDAY <- 8
#> Error: Cannot modify enum

Development

This package uses pre-commit hooks to ensure code quality. To set up the development environment:

# Install pre-commit
pip install pre-commit

# Install the hooks
pre-commit install

# Run hooks manually
pre-commit run --all-files

License

This project is licensed under the MIT License - see the LICENSE file for details.