@spec type_args(term()) :: [term()]

Returns the concrete type-variable bindings for a generic sp_type() node.

When a codec is invoked during type traversal for a parameterised type such as MapSet.t(integer()) or dict:dict(binary(), float()), the sp_type argument is the reference node and type_args/1 returns the list of concrete type arguments in declaration order.

Returns [] when the type has no type variables, or when the codec is invoked directly from a Spectral.encode/decode/schema entry point rather than from mid-traversal dispatch.

Example

# In a codec for MapSet.t(elem):
def encode(:json, mod, {:type, :t, 1}, %MapSet{} = ms, sp_type, _params) do
  case Spectral.Type.type_args(sp_type) do
    [elem_type] ->
      # recursively encode each element using elem_type
    [] ->
      # no type info available, fall back to plain list
      {:ok, MapSet.to_list(ms)}
  end
end