Module quantity 

Represents a quantity with a non-negative value and specified precision.

Quantity is an immutable value type for representing trade sizes, order quantities, and position amounts. It enforces non-negative values and provides fixed-point arithmetic for deterministic calculations.

Arithmetic behavior

Adding or subtracting two Quantity values requires matching effective fixed-point scales. These operations panic on a scale mismatch. Comparisons and hashes account for scale differences without rounding. Without the defi feature, constructors restrict values to a single storage scale.

Operation	Result	Notes
Quantity + Quantity	Quantity	Precision is max of both operands.
Quantity - Quantity	Quantity	Panics if result would be negative.
Quantity * Quantity	Quantity	Precision is max of both operands.
Quantity + Decimal	Decimal
Quantity - Decimal	Decimal
Quantity * Decimal	Decimal
Quantity / Decimal	Decimal
Quantity + f64	f64
Quantity - f64	f64
Quantity * f64	f64
Quantity / f64	f64

Multiplication accepts mixed scales and truncates the result toward zero at the result scale.

Immutability

Quantity is immutable. All arithmetic operations return new instances.

Structs

Quantity

Represents a quantity with a non-negative value and specified precision.

Constants

QUANTITY_MAX

The maximum valid quantity value that can be represented.

QUANTITY_MIN

The minimum valid quantity value that can be represented.

QUANTITY_UNDEF

The sentinel value for an unset or null quantity.

Statics

QUANTITY_RAW_MAX

The maximum raw quantity integer value.

Functions

check_positive_quantity

Checks if the quantity value is positive.

Type Aliases

QuantityRaw