-type buckets() :: [{prometheus_buckets:bucket_bound(), non_neg_integer()}, ...].

-type counter() :: value() | {value()} | {labels(), value()}.

-type gauge() :: value() | {value()} | {labels(), value()}.

-type histogram() ::
          {buckets(), non_neg_integer(), value()} | {labels(), buckets(), non_neg_integer(), value()}.

-type label() :: {label_name(), label_value()}.

-type label_name() :: term().

-type label_value() :: term().

-type labels() :: [label()] | pre_rendered_labels().

-type metrics() :: tmetric() | [tmetric()].

-type pbool() :: prometheus_boolean() | {prometheus_boolean()} | {labels(), prometheus_boolean()}.

-type pre_rendered_labels() :: binary().

-type prometheus_boolean() :: boolean() | number() | list() | undefined.

-type summary() :: {non_neg_integer(), value()} | {labels(), non_neg_integer(), value()}.

-type tmetric() :: gauge() | counter() | untyped() | summary() | histogram() | pbool().

-type untyped() :: value() | {value()} | {labels(), value()}.

-type value() :: float() | integer() | undefined | infinity.