Max Map Type Keys

The number of fields in a type definition that describes a map should be limited to a defined maximum.

Note: Maps with infinite keys (i.e., those that use anything but atoms as keys) are ignored by this rule. The idea is to focus on the map types that represent system entities, database records, etc.

Rationale

Limiting the number of keys in type definitions improves readability and maintainability. Types with too many properties tend to represent too complex structures that can generally be subdivided or split into more appropriate ones that are easier to understand and work with. Keeping map types concise encourages clear, focused logic and makes it easier to navigate the codebase.

Options

• max_keys :: non_neg_integer()
  • default: 25

Example configuration

{elvis_style, max_map_type_keys, #{max_keys => 30}}