Keyword arguments and explicit options

The idea

Keyword arguments name their meaning at the call site. A required keyword has no default, while an optional keyword supplies a default when omitted. This can make configuration clearer than several adjacent booleans or integers whose positions are easy to confuse. A default is still a policy choice: it should describe a sensible missing-argument behavior, not silently override an explicitly supplied value.

Modern Ruby distinguishes keyword arguments from a positional hash. A wrapper that forwards arbitrary calls should preserve positional arguments, keywords, and the block as separate channels. Using **kwargs forwards keyword entries, while *args forwards positional entries. Document which options the public API accepts; swallowing unknown options can hide misspellings that would otherwise be reported as useful argument errors.

def total(values, minimum: 0, multiplier: 1)
  values.select { |n| n >= minimum }.sum * multiplier
end
puts total([1,3,5], minimum: 3, multiplier: 2)

16

The named threshold retains three and five, then the named multiplier doubles their total.