Module Algostream_strategy.Side

The one place trade direction gets converted.

Direction is represented three different ways in the domain layer, and any fill pipeline has to cross all three:

Unifying those three would ripple through most of the test suite, so the representations stay as they are and every conversion goes through this module instead. If a sign flips somewhere, it flipped here.

val of_trade_side : [ `Buy | `Sell ] -> t
val to_trade_side : t -> [ `Buy | `Sell ]
val sign : t -> float

Buy → 1.0, Sell → -1.0.

val signed : t -> qty:float -> float

signed side ~qty applies sign to a positive quantity, producing the signed value Portfolio.add_trade expects. A negative qty is treated as its magnitude — the side argument is authoritative, so callers cannot accidentally double-negate.

val of_signed : float -> t option

Recover a side from a signed quantity. None at exactly zero, where there is no direction.

val opposite : t -> t
val to_string : t -> string
val equal : t -> t -> bool