Numeric Format

All numbers should be formatted according to the regular expression(s) provided.

Rationale

This is a convention aimed at ensuring consistency, rather than a coding issue.

By default, all number formats are valid in Erlang — but inconsistent use of underscores or base notation can make numbers harder to read or visually misleading. For example, 1_23_456_7890 is technically valid but non-standard and visually confusing. This rule allows teams to define acceptable numeric formats (e.g., 1234567890 or 1_234_567_890) using regular expressions, and receive warnings when deviations occur.

Options

• regex :: string()
  • default: ".*"

• int_regex :: string() | same

  • default: same
  • same - use the generic regex

• float_regex :: string() | same

  • default: same
  • same - use the generic regex

Example configuration

{elvis_style, numeric_format, #{
    regex => ".*",
    int_regex => same,
    float_regex => same
}}