class BinData::Struct

def field_names(include_hidden = false)

in the listing.
object. +include_hidden+ specifies whether to include hidden names
Returns a list of the names of all fields accessible through this

def field_names(include_hidden = false)
  if include_hidden
    @field_names.compact
  else
    hidden = get_parameter(:hide) || []
    @field_names.compact - hidden
  end
end