DpExchange.Core.Types.Funding (DpExchangeCore v0.1.52)

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A perpetual's funding: what was paid, what is projected, and when the next one lands.

Settled and estimated are different facts

:amount is funding that has happened — a payment between longs and shorts at a funding time that has passed. :estimated_amount is the venue's projection for the next one, and it moves continuously until the moment it settles.

They are separate fields for the same reason realised and unrealised P&L are on Types.Position: one is a fact and the other is an opinion, and a caller that books an estimate has booked a number that had not happened. A venue's own response carries both — fundingAmount: -1.50991 beside estimatedFundingAmount: -2.10595, differing by 40% — which is precisely how wrong a caller reading "the funding" would be.

Sign is the venue's, and it means direction

Funding is a payment between sides. A negative amount means one side paid the other, and which is which is a venue convention this layer does not reinterpret. The sign is carried through unchanged; a package that normalised it would be asserting a convention the venue did not state.

:next_funding_at is a scheduling fact

A caller holding a perpetual across a funding time pays or receives at that instant. Knowing when it is, is the difference between choosing to hold the position and discovering the payment afterwards.

Summary

Types

t()

Functions

new(attrs)

Builds a t/0, failing closed if a required field is absent or nil.

Types

t()

@type t() :: %DpExchange.Core.Types.Funding{
  amount: Decimal.t() | nil,
  estimated_amount: Decimal.t() | nil,
  funded_at: DateTime.t() | nil,
  next_funding_at: DateTime.t() | nil,
  provider: atom(),
  symbol: String.t()
}

Functions

new(attrs)

@spec new(keyword() | map()) :: t()

Builds a t/0, failing closed if a required field is absent or nil.

@enforce_keys guards presence, not nil — see DpExchange.Core.Types.Validate.